Category: Class 12

Tamilnadu State Board New Syllabus Samacheer Kalvi 12th Business Maths Guide Pdf Chapter 2 Integral Calculus I Ex 2.2 Text Book Back Questions and Answers, Notes.

Tamilnadu Samacheer Kalvi 12th Business Maths Solutions Chapter 2 Integral Calculus I Ex 2.2

Question 1.
Integrate the following with respect to x.
[\(\sqrt { 2x}\) – \(\frac { 1 }{\sqrt { 2x}}\)]²
Solution:

Question 2.
\(\frac { x^4+x^2+2 }{(x-1)}\)
Solution:

Question 3.
\(\frac { x^3 }{x+2}\)
Solution:

Question 4.
\(\frac { x^3+3x^2-7x+11 }{x+5}\)
Solution:

Question 5.
\(\frac { 3x+2 }{(x-2)(x-3)}\)
Solution:
By partial fraction

Question 6.
\(\frac { 4x^2+2x+6 }{(x+1)^2(x-3)}\)
Solution:
By partial fraction

⇒ 4x² + 2x + 6 = A (x + 1)² + B (x – 3) (x + 1) + c (x – 3)
Put x = 3
4(9) + 2(3) + 6 = A(4)²
36 + 6 + 6 = 16A ⇒ A = \(\frac { 48 }{16}\)
A = 3
Put x = -1
4(1) + 2(-1) + 6 = C(-4)
4 – 2 + 6 = -4C ⇒ -4c = 8
C = -2
Put x = 0
6 = A(1) + B(-3) + C(-3)
6 = 3(1) – 3B + (-2) (-3)
6 = 3 – 3B + 6 ⇒ 3B = 3
B = 1

Question 7.
\(\frac { 3x^2-2x+5}{(x-1)(x^2+5)}\)
Solution:

Question 8.
Given f'(x) = \(\frac { 1 }{x}\) and f (1) = \(\frac { 1 }{π}\), then find f(x)
Solution:
f'(x) = \(\frac { 1 }{x}\)
f(x) = ∫f'(x) dx = ∫\(\frac { 1 }{x}\) dx
f(x) = log|x| + c
f(1) = π/4 ⇒ log|1| + c = π/4.
⇒ 0 + c = π/4
∴ c = π/4
∴ Required f (x) = log |x| + π/4

Tamilnadu State Board New Syllabus Samacheer Kalvi 12th Chemistry Guide Pdf Chapter 11 Hydroxy Compounds and Ethers Text Book Back Questions and Answers, Notes.

Tamilnadu Samacheer Kalvi 12th Chemistry Solutions Chapter 11 Hydroxy Compounds and Ethers

12th Chemistry Guide Hydroxy Compounds and Ethers Text Book Questions and Answers

Part – I Text Book Evaluation

I. Choose the correct answer

Question 1.
An alcohol (x) gives blue colour in victormayer’s test and 3.7g of X when treated with metallic sodium liberates 560 mL of hydrogen at 273 K and 1 atm pressure what will be the possible structure of X?
(a) CH₃ CH (OH) CH₂CH₃
(b) CH₃ – CH(OH) – CH₃
(c) CH₃ – C (OH) (CH₃)₂
(d) CH₃ – CH₂ – CH (OH) – CH₂ – CH₃
Answer:
(a) CH₃ CH (OH) CH₂CH₃
Hint:
2R – OH + Na → 2RONa + 2H₂ ↑ 2 moles of alcohol gives 1 mole of H₂ which occupies
22.4L at 273K and 1 atm
number of moles of alcohol = \(\frac{2 \text { moles of } \mathrm{R}-\mathrm{OH}}{22.4 \mathrm{L} \text { of } \mathrm{H}_{2}}\) x 560 mL = 0.05 moles
number of moles = \(\frac{\text { mass }}{\text { molar mass }}\)
= molar mass = \(\frac{3.7}{0.05}\) = 74 g mol^-1
General formula for
R – OH C_n H_2n+1 – OH
n(12) + (2n+1) (1) + 16 +1 = 74
14n = 74 – 18
14n = 56
n = \(\frac { 56 }{ 4 }\) = 4
The 2° alcohol which contains 4 carbon is CH_n CH(OH)CH₂ CH₃

Question 2.
Which of the following compounds on reaction with methyl magnesium bromide will give tertiary alcohol.
(a) benzaldehyde
(b) propanoic acid
(c) methyl propanoate
(d) acetaldehyde
Answer:
(c) methyl propanoate
Solution:

Question 3.


Answer:
a
Solution:
hydro boration – Anti markownikoff product
i.e CH₃ – CH₂ – CH – CH₂ – CH₂ – OH

Question 4.
In the reaction sequence, Ethane

Ethan – 1, 2 – diol. A and X respectively are ………….
(a) Chioroethane and NaOH
(b) ethanol and H₂SO₄
(c) 2 – chloroethan – 1 – ol and NaHCO₃
(d) ethanol and H₂O
Answer:
(c) 2 – chloroethan – 1 – ol and NaHCO₃\

Solution:

Question 5.
Which one of the following is the strongest acid ………..
(a) 2 – nitrophenol
(b) 4 – chlorophenol
(c) 4 – nitrophenol
(d) 3 – nitrophenol
Answer:
(c) 4 – nitrophenol

Question 6.

on treatment with Con. H₂SO₄, predominately gives ……………..


Answer:
b
Solution:

Question 7.
Carbolic acid is …………..
(a) Phenol
(b) Picric acid
(c) benzoic acid
(d) phenylacetic acid
Answer:
(a) Phenol

Question 8.
Which one of the following will react with phenol to give salicyladehyde after hydrolysis …………..
(a) Dichioro methane
(b) trichioroethane
(c) trichloro methane
(d) CO₂
Answer:
(c) trichloro methane (Riemer Tiemann reaction)

Question 9.

(a) (CH₃)₃ CCH = CH₂
(b) (CH₃)₂ C = C (CH₃)₂
(c) CH₂ = C(CH₃)CH₂ – CH₂ – CH₃
(d) CH₂ = C (CH₃) – CH₂ – CH₂ – CH₃
Answer:
(b) (CH₃)₂ C = C (CH₃)₂
Solution:

Question 10.
The correct IUPAC name of the compound,

(a) 4 – chloro – 2, 3 – dimethyl pentan – 1 – ol
(b) 2, 3 – dimethyl – 4 – chloropentan – 1 – ol
(c) 2, 3, 4 – trimethyl – 4 – chiorobutan – 1 – ol
(d) 4 – chioro – 2, 3, 4 – trimethyl pentan – 1 – ol
Answer:
(a) 4 – chloro – 2, 3 – dimethyl pentan – 1 – ol

Question 11.
Assertion: Phenol is more acidic than ethanol
Reason: Phenoxide ion is resonance stabilized
(a) if both assertion and reason are true and reason is the correct explanation of assertion.
(b) if both assertion and reason are true but reason is not the correct explanation of assertion.
(c) assertion is true but reason is false
(d) both assertion and reason are false.
Answer:
if both assertion and reason are true and reason is the correct explanation of assertion.

Question 12.
In the reaction Ethanol

is ………………
(a) ethane
(b) ethoxyethane
(c) ethylbisuiphite
(d) ethanol
Answer:
(d) ethanol
Solution:

Question 13.
The reaction

can be classified as
(a) dehydration
(b) Williams on alcohol synthesis
(c) Williamson ether synthesis
(d) dehydrogenation of alcohol
Answer:
(c) Williamson ether synthesis
Solution:
Cyclic alcohol → sodium cyclic alkoxide → Williamson ether synthesis

Question 14.
Isoprophylbcnzene on air oxidation in the presence of dilute acid gives …………
(a) C₆H₅COOH
(b) C₆H₅COCH₃
(c) C₆H₅COC₆H₅
(d) C₆H₅ – OH
Answer:
(a) C₆H₅ – OH (phenol)

Question 15.
Assertion: Phenol is more reactive than benzene towards electrophilic substitution reaction
Reason: In the case of phenol. the intermediate arenium ion is more stabilized by resonance.
(a) if both assertion and reason are true and reason is the correct explanation of assertion.
(b) if both assertion and reason are true but reason is not the correct explanation of assertion.
(c) assertion is true but reason is false
(d) both assertion and reason are false,.
Answer:
(a) if both assertion and reason are true and reason is the correct explanation of assertion.

Question 16.
HO CH₂ CH₂ – OH on heating with periodic acid gives ………..
(a) methanoic acid
(b) Glyoxal
(c) methanol
(d) CO₂
Answer:
(c) methanol

Question 17.
Which of the following compound can be used as artireeze in automobile radiators?
(a) methanol
(b) ethanol
(c) Neopentyl alcohol
(d) ethan -1, 2-diol
Answer:
(d) ethan -1, 2-diol

Question 18.
The reaction

is an example of …………..
(a) Wurtz reaction
(b) cyclic reaction
(c) Williamson reaction
(d) Kolbe reactions
Answer:
(c) Kolbe reactions

Question 19.
One mole of an organic compound (A) with the formula C₃H₈O reacts completely with two moles of HI to form X and Y. When Y is boiled with aqueous alkali it forms Z. Z answers the iodoform test. The compound (A) is ……………
(a) propan – 2 – ol
(b) propan- 1- ol
(c) ethoxy ethane
(d) methoxy ethane
Answer:
(d) methoxy ethane
Solution:

Question 20.
Among the following ethers which one will produce methyl alcohol on treatment with hot HI?

Answer:
a
Solution:

Question 21.
Williamson synthesis of preparing dimethyl ether is a / an
(a) SN¹ reactions
(b) SN² reaction
(c) electrophilic addition
(d) electrophilic substitution
Answer:
(b) SN² reaction

Question 22.
On reacting with neutral ferric chloride, phenol gives
(a) red colour
(b) violet colour
(c) dark green colour
(d) no colouration
Answer:
(b) violet colour

II. Short Answer

Question 1.
IdentIfy the product (s) is/are formed when 1 – methoxy propane is heated with excess HI. Name the mechanism involved in the reaction.
Answer:

Ethers having primary alkyl group undergo \(\mathrm{S}_{\mathrm{N}}^{2}\) reaction

Question 2.
Draw the major product formed when 1 – ethoxyprop – 1 – ene is heated with one equivalent of HI
Answer:

Question 3.
Suggest a suitable reagent to prepare secondary alcohol with an identical groups using a Grignard reagent.
Answer:

Question 4.
What is the major product obtained when two moles of ethyl magnesium bromide is treated with methyl benzoate followed by acid hydrolysis
Answer:

Question 5.
Predict the major product, when 2-methyl but – 2 – ene is converted into alcohol in each of the following methods.

1. Acid-catalyzed hydration
2. Hydroboration
3. Hydroxylation using bayers reagent

Answer:

Question 6.
Arrange the following in the increasing order of their boiling point and give a reason for your ordering

1. Butan – 2 – ol, Butan – 1 – SI, 2 – methylpropan – 2 – ol
2. Propan – 1 – ol, propan – 1, 2, 3 – triol, propan – 1, 3 – diol, propan – 2 – ol

Answer:
1. Boiling points increases regularly as the molecular mass increases due to a corresponding increase in their Van der Waal’s force of attraction. Among isomeric alcohols, 2° – alcohols have lower boiling points than 1° – alcohols due to a corresponding decrease in the extent

of H-bonding because of steric hindrance. Thus the boiling point of Butan – 2 – ol is lower than that of Butan – 1 – ol. Overall increasing order of boiling points is, 2 – methyl propane – 2 – ol < Butan – 2 – ol < Butan – 1 – ol

2. 2°-alcohols have lower boiling points than 1° – alcohols due to a corresponding decrease in the extent of H – bonding because of steric hindrance. Therefore Propan – 1 – ol has higher boiling point than Propan – 2 – ol. The hydrogen group increases, boiling point also increases. Overall increasing order of boiling points is, propan – 2 – ol < Propan – 1 – ol < propan – 1, 3 – diol < propan -1, 2, 3 – triol

Question 7.
Can we use nucleophiles such as NH₃, CH₃O for the Nucleophilic substitution of alcohols
Answer:
1. Increasing order of nucleophilicity,
NH₃ < – OH^⊕ < CH₃O^⊖-

2. Higher electron density will increase the nucleophilicity.

3. Negatively charged species are almost always more nucleophiles than neutral species.

4. RO^⊖ has an alkyl group attached, allowing a greater amount of polarizability. This means oxygen’s lone pairs will be more readily available to reach in RO^⊖ than in OH^⊖. Hence CH₃O – is the better nucleophile for the nucleophilic substitution of alcohols. NH₃ cannot act as nucleophiles for the nucleophilic substitution of alcohols.

Question 8.
Is it possible to oxidise t – butyl alcohol using acidified dichromate to form a carbonyic compound.
Answer:
3° – alcohols do not undergo oxidation reaction under normal conditions, but at elevated temperature, under strong oxidising agent cleavage of C – C bond takes place to give a mixture of carboxylic acid.

Yes, it is possible. t – butyl alcohol is readily oxidsing in acidic solution (K₂Cr₂O₇ / H₂SO₄) to a mixture of a ketone and an acid each containing lesser number of carbon atoms than the original alcohol. The oxidation presumably occur via alkenes formed through dehydration of alcohols under acidic conditions.

Question 9.
What happens when 1 – phenyl ethanol is treated with acidified KMnO₄.
Answer:
1 – phenyl ethanol reacts with acidified KMnO₄ to give Acetophenone.

Question 10.
Write the mechanism of acid catalysed dehydration of ethanol to give ethene.
Answer:

Question 11.
How is phenol prepared form

1. chloro benzene
2. isopropyl benzene

Answer:

Question 12.
Explain Kolbe’s reaction
Answer:
Kolbe’s (or) Kolbe’s Schmitt reaction:
In this reaction, phenol is first converted into sodium phenoxide which is more reactive than phenol towards electrophilic substitution reaction with CO₂. Treatment of sodium phenoxide with CO₂ at 400K, 4 -7 bar pressure followed by acid hydrolysis gives salicylic acid.

Question 13.
Writes the chemical equation for Williamson synthesis of 2 – ethoxy – 2 – methyl pentane starting from ethanol and 2 – methyl pentan – 2 – ol
Answer:
A tertiary alkoxide and primary alkyl halide easily undergo williamson ether synthesis

Question 14.
Write the structure of the aldehyde, carboxylic acid and ester that yield 4 – methylpent – 2 – en – 1 – ol.
Answer:

Question 15.
What is metamerism? Give the structure and IUPAC name of metamers of 2 – methoxy propane
Answer:
Metamerism:
It is a special type of isomerism in which molecules with same formula, same functional group, but different only in the nature of the alkyl group attached to oxygen.

Question 16.
How are the following conversions effected

1. benzyl chlorjde to benzyl alcohol
2. benzyl alcohol to benzoic acid

Answer:

Question 17.
Complete the following reactions

Answer:

Question 18.
O.44g of a monohydric alcohol when added to methyl magnesium iodide in ether liberates at STP 112 cm³ of methane with PCC the same alcohol form a carbonyl compound that answers silver mirror test. Identify the compound.

C_nH_2n+1+OH
⇒ n x 12+ (2n + 1) x 1 + 1 x 16 + 1 x 1 = 88
12n + 2n + 1 + 16 + 1 = 88
14n + 18 = 88
14n = 88 – 18
14n = 70
n = 70/14 = 5
Answer:

Question 19.
Complete the following reactions

Answer:

(According to Saytzeff s rule, during intramolecular dehydration, if there is a possibility to form C = C bond at different locations, the preferred location is the one that gives the more substituted alkene je, the stable alkene).

Question 20.
Phenol is distilled with Zn dust gives (A) followed by Friedel – crafts alkylation with propyl chloride to give a compound B, B on oxidation gives (C). Identify A,B and C.
Answer:

Note:
Carbon directly attached to the aromatic riñg is called benzylic carbon.
If there is hydrogen attached to benzylic carbon it will undergo oxidation.

Question 21.

Identify A, B, C, D and write the complete equation.
Answer:

Question 22.
What will be the product for the following reaction

Answer:

Question 23.
How will you convert acetylene into n – butyl alcohol.
Answer:

Question 24.
Predict the product A, B, X and Y in the following sequence of reaction

Answer:

Question 25.
3,3 – dimethyl butane – 2 – ol on treatment with conc. H₂SO₄ to give tetramethyl ethylene as a major product. Suggest suitable mechanisms.
Answer:

III. Evaluate yourself

Question 1.
Classify the following alcohols as 1⁰, 2⁰, and 3⁰ and give their IUPAC Names.

Answer:

Question 2.
Write all the possible isomers of alcohol having the molecular formula C₁₅H₁₂O and their IUPAC names.
Answer:
Eight isomers are possible for C₁₅H₁₂O. They are,

Question 3.
Suggest a suitable carbonyl compound for the preparation of pent – 2 – en – 1 ol using LiAlH₄.
Answer:

Question 4.
2 – methylpropan – 2 – ene

Answer:

Question 5.
How will you prepare the following using a Grignard reagent?

1. t – butyl alcohol
2. allyl alcohol

Answer:

Question 6.
Identify the products in the following reactions. Write their IUPAC names and mention the mechanism involved in the reactions.

Answer:

Question 7.
What is the major product obtained when 2, 3 – dimethyl pentan – 3 – ol is heated in the presence of H₂SO₄
Answer:

Question 8.
Which of the following set of reactants will give 1 – methoxy – 4 – nitrobenzene.

Answer:

Question 9.
What happens when m – cresol is treated with an acidic solution of sodium dichromate?
Answer:

Question 10.
When phenol is treated with propan – 2 – ol in the presence of HF, Friedel – Craft reaction takes place. Identify the products.
Answer:

Question 11.
Given the IUPAC name for the following ethers and classify them as simple or mixed.
Answer:

Question 12.
1. Which of the following reaction will give 1 – methoxy – 4 – nitrobenzene.

1. 4 – nitro – 1 – bromobenzene + sodium methoxide.
2. 4 – nitrosodium phenoxide + bromomethane

Answer:
4-nitrosodium phenoxide + bromo methane → 1 – methoxy – 4 – nitrobenzene

Reason: 4 – nitro -1- brornobnzene + sodium methoxide can not be used, because bromine is strongly bonded to carbon atom of hcnzcne ring and it can not be replaced easily.

Question 13.
Arrange the following compounds in the increasing order of their acid strength. propan – 1 – ol, 2, 4, 6 – trinitroptienol, 3 – nitrophenol, 3,5 – dinitrophenol, phenol, 4 – methyl phenol.
Answer:
Phenols are stronger acids than alcohols because the phenoxide ion left after the removal of proton is stabilized by resonance while the alkoxide ion left after the removal of a proton from alcohol is not stabilized. Thus propan – 1 – ol is much weaker acid than any phenol.

Thus propan- 1 – ol is a much weaker acid than any phenol. We know that electron-donating groups decrease the acidic character and stronger is the electron-donating group, weaker is the phenol.

Compare to propan – 1 – ol, 4 – methyl phenol is a stronger acidic character. But comparing phenol and 4-methyl phenol, phenol is stronger acidic. Since electron-withdrawing groups increase the acidic character of phenols and the effect is more pronounced at the para position than at the meta position.

Therefore 4 – nitrophenol is a stronger acid than 3 – nitro phenol. Further as the number of electron-withdrawing groups increases the acidic strength further increases. Therefore 2, 4, 6 – trinitrophenol is a stronger acid than 3, 5 – dinitrophenol. It may be noted here that although the two nitro groups in 3, 5 – dinitrophenol are at m – position with respect to OH group,

their combined effect is however greater than one nitro group at p – position. Therefore 3, 5 – dinitrophenol is a stronger acid than 4-nitro phenol. Thus, the overall increasing order of acid strength is. Propan – 1 – 01 < 4 – methyl phenol < phenol < 3 – nitrophenol < 3, 5 – dinitrophenol < 2, 4, 6 – trinitrophenol.

Question 14.
1 mole of HI is allowed to react with t – butyl methylether. Identify the product and write down the mechanism of the reaction.
Answer:

The reaction involves the protonation of oxygen which is followed by the SN1 mechanism.
The products are t-butvl iodide and methyl alcohol.

12th Chemistry Guide Hydroxy Compounds and Ethers Additional Questions and Answers

Part – II – Additional Questions

I. Choose the correct answer

Question 1.
In ethanol the – OH group is attached to hybridised carbon
a) sp
b) sp²
c) sp³
d) dsp²
Ans :
c) sp³

Question 2.
In Vinyl alcohol the -OH group is attached to hvbridised carbon
a) sp
b) sp²
c) sp³
d) dsp²
Ans :
b) sp²

Question 3.
Sorbitol is
a) monohydric alcohol
b) dihydric alcohol
c) trihydric alcohol
d) hexa hydric alcohol
Answer:
d) hexa hydric alcohol

Question 4.
The IUPAC name of sorbitol is
a) Ethan -1, 2 – diol
b) Propan – 1, 2, 3 – triol
c) Hexan – 1, 2, 3, 4, 5, 6 – hexol
d) Ethenol
Answer:
c) Hexan – 1, 2, 3,4, 5, 6 – hexol

Question 5.

a) prop – 2 – en – 1 – ol
b) 2 – methyl but – 3 – en – 2 ol
c) 3 – methyl but – 1 – en – 3 – ol
d) 1,1 – di methyl prop – 2 – en – 1 – ol
Answer:
b) 2 – methyl but – 3 – en – 2 ol

Question 6.
The C – O – H bond angle in methanol is
a) 107°
b) 109°.5°
c) 108.9°
d) 104°
Answer:
c) 108.9°

Question 7.
CH₃-CH₂-a + NaOH → CH₃-CH₂-OH + NaCl This reaction follows mechanism
a) \(S_{N}^{1}[latex]
b) [latex]S_{N}^{2}\)
c) E¹
d) E²
Answer:
b) \(S_{N}^{2}\)

Question 8.
Conversion of isobutyl chloride and isopropyl chloride into isobutyl alcohol and isopropyl alcohol respectively using dilute aquous NaOH follow the mechnisms

Answer:
c)
Reason : Isobutylchloride – Primary alkyl halide – \(S_{N}^{2}\) mechanism.
Iso propyl chloride – Secondary alkyl halide – Sjsj mechanism.
\(S_{N}^{1}\)

Question 9.
Addition of water across the double bond
of an unsymmetrical alkene follows
a) Saytzeffs rule
b) Markownikoff’s rule
c) anti Markownikoff’s rule
d) Popoff’s rule
Answer:
b) Markownikoff’s rule

Question 10.
Hydroboration of an alkene follows
a) Saytzeff’s rule
b) Markownikoff’s rule
c) anti Markownikoff’s rule
d) Popoff’s rule
Answer:
c) anti – Markownikoff’s rule

Question 11.
Addition of water to 2-methyl propene in
presence of cone, sulphuric acid gives
a) 2-propanol
b) 2 – methyl – 2 – propanol
c) 2 – methyl – 1 – propanol
d) 2 – butanol
Answer:
b) 2 – methyl – 2 – propanol

Question 12.
2 – methyl propene reacts with diborane followed by H2O2 in presence of NaOH gives
a) 2 – proponol
b) 2 – methyl – 2 – propanol
c) 2 – methyl – 1 – propanol
d) 2 – butanol
Answer:
c) 2 – methyl -1 – propanol

Question 13.
To prepare a primary alcohol a Grignard reagent must be reacted with
a) HCHO
b) RCHO
c) RCOR
d) RNH₂
Answer:
a) HCHO

Question 14.
To prepare a secondary alcohol a
Grignard reagent must be reacted with
a) HCHO
b) RCHO
c) RCOR
d) RNH₂
Answer:
b) RCHO

Question 15.
To prepare a tertiary alcohol a Grignard reagent must be reacted with
a) HCHO
b) RCHO
c) RCOR
d) RNH₂
Ans:
b) RCOR

Question 16.
Phenyl magnesium bromide reacts with formaldehyde followed by hydrolysis gives
a) phenol
b) Benzyl alcohol
c) Benzaldehyde
d) Benzoic acid
Answer:
b) Benzyl alcohol

Question 17.
Name the product obtained when 1 mole of methyl magnesium bromide reacts with ethyl methanoate
a) propan -2- ol
b) propan – 1 – ol
c) ethanal
d) ethanol
Answer:
c) ethanal

Question 18.

The reducing agent X is
a) Ramey Ni
b) NaBH₄
c) LiA/H₄
d) Na – Hg
Answer:
b) NaBH₄

Question 19.
The best reducing agent to prepare unsaturated alcohols from unsaturated carbonyl compounds is
a) Raney Ni
b) NaBH₄
c) LiA/H₄
d) both (b) & (c)
Answer:
d) both (b) & (c)

Question 20.
Ethene is converted into ethylene glycol by treating with
a) acidified potassium dichromate
b) alkaline potassium permanganate
c) Chromyl chloride
d) nitric acid
Answer:
b) alkaline potassium permanganate

Question 21.
Cold dilute alkaline potassium permanganate is called as
a) Fenton’s reagent
b) Tollen’s reagent
c) Baeyer’s reagent
d) Schiff’s reagent
Answer:
c) Baeyer’s reagent

Question 22.
Glyceryl palmitate on alkaline hydrolysis gives
a) glycerol and soap
b) glycerol and sodium palmitate
c) glycerol and sodium hexadentate
d) all the above
Answer:
d) all the above

Question 23.
The preparation of glycerol and soap from oils and fats is known as
a) esterification
b) saponification
c) hydroboration
d) transesterification
Answer:
b) saponification

Question 24.
Lucas reagent is
a) dil HCl & ZnCl₂
b) Cone. HCl & anhydrous ZnCl₂
c) dil H₂SO₄ & AlCl₃
d) Conc. H2SO4 & anhydrous AlCl3
Answer:
b) Cone. HCl & anhydrous ZnCl₂

Question 25.
Which among the following will give immediate turbidity with Lucas reagent?
a) propan – 2 – ol
b) propan – 1 – ol
c) 2 – methyl propan – 2 – ol
d) 2 – methyl propan – 1 – ol
Answer:
c) 2 – methyl propan – 2 – ol
Hint: A teritary alcohol gives immediate turbidity

Question 26.
In Victor Meyer’s test, the alcohol which
gives blue colour is
a) propan – 2 – ol
b) propan – 1 – ol
c) 2 – methyl propan – 2 – ol
d) 2 – methyl propan – 1 – ol
Answer:
a) propan – 2 – ol
Hint: A secondary alcohol gives blue colour.

Question 27.
In the given equation


Answer:
c

Question 28.
Among butyl alcohols which one have the lowest boiling point?
a) n-butyl alcohol
b) isobutyl alcohol
c) sec-butyl alcohol
d) ter – butyl alcohol
Answer:
d) ter – butyl alcohol Hint: Increasing order of boiling point is 30 < 2° < 1°

Question 29.
Which among the alcohol has a higher boiling point?
a) n-butyl alcohol
b) n-propyl alcohol
c) ethyl alcohol
d) methyl alcohol
Answer:
a) n-butyl alcohol
Hint: As molecular weight of the alcohol increases, boiling point increases.

Question 30.
Which among the following is less soluble in water?
a) n-butyl alcohol
b) n-propyl alcohol
c) ethyl alcohol
d) methyl alcohol
Answer:
a) n-butyl alcohol Hint: As the molecular weight increases, the solubility of alcohol decreases.

Question 31.
Conversion of alcohols into alkyl halide is an example of
a) Nucleophilic addition
b) Nucleophilic substitution
c) Electrophilic addition
d) Electrophilic substitution
Answer:
b) Nucleophilic substitution

Question 32.
Conversion of 2 – methyl – 1 – propanol into 2 – methyl – 1 – bromopropane is …………. reaction
a) SN²
b) SN¹
c) E²
d) E¹
Answer:
a) SN²

Question 33.
Primary alcohols undergo dehydration by mechanism
a) SN²
b) SN¹
c) E²
d) E¹
Ans:
d) E¹

Question 34.
2 – methyl – 2 – propanol when reacted with cone. H₂SO₄ gives 2 – methyl propene. This reaction follows mechanism
a) SN²
b) SN¹
c) E²
d) E¹
Answer:
d) E¹

Question 35.
During intramolecular dehydration of 3, 3 – dimethyl – 2 – butanol the major product obtained is
a) 2, 3 – dimethyl but – 1 – ene
b) 2, 3 – dimethyl but – 2 – ene
c) 3, 3 – dimethyl but – 1 – ene
d) 3, 3 – dimethyl but – 2 – ene
Answer:
b) 2, 3 – dimethyl but – 2 – ene

Question 36.
The major product obtained when phenol reacts with con.H₂SO₄ at 280 K is
a) Salicyclic acid
b) picric acid
c) o-phenol sulphonic acid
d) p-phenol sulphonic acid
Answer:
c) o-phenol sulphonic acid

Question 37.
During intramolecular dehydration of alcohols say tzeff’s rule favours the formation of
a) unstable alkenes
b) less substituted alkenes
c) more substituted alkenes
d) none of the above
Answer:
c) more substituted alkenes

Question 38.
To stop the oxidation reaction of alcohols at the aldehyde / ketone stage…………..is used as an oxidising agent
a) Pottassium permanganate
b) Py ridinium chloro chromate (PCC)
c) Potassium di chromate
d) Sodium di chromate
Answer:
b) pyridinium chloro chromate (PCC)

Question 39.
In Swern oxidation of alcohols into aldehydes/ketones the oxidising agent used is
a) Pyridinium chlorochromate (PCC)
b) Dimethyl sulfoxide (DMSO)
c) Alkaline potassium permanganate (Baeyer’s reagent)
d) Ferrous sulphate / H2O2 (Fenton’s reagent)
Answer:
b) Dimethyl sulfoxide (DMSO)

Question 40.
To detoxify the alcohol produced in animals by the fermentaion of food, the oxidising agent used is
a) ADH
b) ADP
c) NAD
d) ATP
Answer:
c) NAD

Question 41.
The catalyst which catalyses the oxidation of toxic alcohols into non-toxic aldehyde in animals is
a) ADH
b) ADP
c) NAD
d) ATP
Answer:
a) ADH

Question 42.
When ethan-1, 2-diol is heated with anhydrous ZnCl₂ under pressure it gives
a) Ethanol
b) Ethanal
c) Ethanoic acid
d) Ethene
Ans:
b) Ethanal

Question 43.
Glycerol can be oxidised to meso oxalic acid by
a) dii HNO₃
b) HIO₄
c) Bismuth nitrate
d) Fenton’s reagent
Answer:
c) Bismuth nitrate

Question 44.
The alcohol used in the manufacture of dynamite is
a) methanol
b) ethanol
c) ethv lene glycol
d) glycerol
Answer:
d) glycerol

Question 45.
The correct order of acidic nature of alcohols is
a) Ethanol < propan – 2 – ol < 2 – methyl propan – 2- ol
b) Propan – 2 – ol < Ethanol < 2 – methyl propan — 2 — ol
c) 2 – methyl propan – 2 – ol < Ethanol < propan – 2 – ol
d) 2 – methyl propan – 2 — ol Answer:
d) 2 – methyl propan – 2 – ol

Question 46.
1, 3 – dihydroxy benzene is commonly
known as
a) Cresol
b) Catechol
c) Resorcinol
d) Quinol
Answer:
c) Resorcinol

Question 47.
The JUPAC name of pyrogallol is
a) 1, 2, 3 — trthydroxy benzene
h) 1, 2, 4 — trihydroxy beneze
c) 1, 3, 5 — trihydroxv benzene
d) 1, 4, 5 — tri hydroxy benzene .
Answer:
a) 1, 2, 3 — trihydroxy benzene

Question 48.
Oricinol is
a) 1, 2 – dihydroxy benzene
h) 3 — methyl phenol :
c) 3, 5 — dihydroxy toluene
d) 3, 5 — dimethyl toluene
Answer:
c) 3, 5 – dihydroxy toluene

Question 49.
Which of the following reaction will give ether?

Ans:
d) All of the above

Question 50.
Phenol on oxidation with acidified K₂Cr₂O₇gives
a) 1, 4 – dihydroxy benzene
b) 1,4- benzoquinone
c) cyclohexanol
d) cumene
Answer:
b) 1,4- benzoquinone

Question 51.
Which among the following is a simple ether?
a) 1 – methoxy propane
b) 2 – methoxy propane
c) methoxy methane
d) methoxv benzene
Answer:
c) methoxy methane

Question 52.
The oxygen atom of ether is
hybridised
a) sp
b) sp²
c) sp³
d) dsp²
Answer:
c) sp³

Question 53.
Williamson’s synthesis is an example of
a) nucleophilic addition
b) nucleophilic substitution
c) electrophilic addition
d) electrophilic substitution
Answer:
b) nucleophilic substitution

Question 54.
Which among the following is more reactive
towards ethers?
a) HF
b) HCl
c) HBr
d) HI
Answer:
d) HI

Question 55.
The products obtained when methoxy
ethane reacted with one mole of HI are
a) methanol & iodoethane
h) iodomethane & ethanol
c) iodomethane & jodo ethane
d) Methanol & ethanol
Answer:
b) iodomethane & ethanol

Question 56.
Which is used as a precursor to the synthesis of perfumes and insecticide pheromones?
a) Phenol
b) Phenoxy methane
c) methoxy benzene
d) Ethoxy benzene
Answer:
c) methoxy benzene

Question 57.
According to Lewis concept of acids and bases an ether is
a) acidic
b) basic
c) neutral
d) amphoteric
Answer:
b) basic

Question 58.

a) CH₃COCH₃
b) C₂H₅OH
c) CH₃-CH(OH)CH₃
d) CH₃CHO
Answer:
c) CH₃-CH(OH)CH₃

Question 59.

a)Propan-1,3-diol
b) Ethan -1,2- diol
c) Propan -1,2,3- Triol
d) Ethanal
Answer:
b) Ethan -1,2- diol

Question 60.
Which of the following has lowest boiling point?
a) phenol
b) O-nitro phenol
c) m-nitro phenol
d) p-nitro phenol
Answer:
b) O-nitro phenol
Hint: O – nitrophenol has intramolecular hydrogen bonding while others intermolecular hydrogen bonding.

II. Assertion and Reason

Question 1.
Assertion : Tertiary alcohols undergo dehydration more readily than primary alcohol.
Reason : Tertiary alcohols are less acidic than primary alcohol.
a) Both assertion and reason are true and reason is the correct explanation of assertion
b) Both assertion and reason are true but reason is not the correct explanation of assertion
c) Assertion is true but reason is false.
d) Both assertion and reason are false.
Answer:
b) Both assertion and reason are true but reason is not the correct explanation of assertion

Question 2.
Assertion (A) : Alcohols can act as Bronsted acids
Reason (R) : It is due to the presence of unshared electron pairs on oxygen which make them proton acceptors.
a) Both (A) and (R) are correct, R explain A.
b) Both (A) and (R) are correct, R does not explain A.
c) (A) is correct but R is correct.
d) (A) is wrong but R is correct.
Answer:
d) (A) is wrong but R is correct Correct Reason (A) : Alcohols can act as Bronsted bases.

Question 3.
Assertion (A) : Phenol is more acidic than aliphatic alcohols
Reason (R) : Alkyl substituted phenols show a decreased acidity due to the electron releasing +1 effect of alkyl group.
a) Both (A) and (R) are correct, R explain A.
b) Both (A) and (R) are correct, R does not explain A.
c) (A) is correct but R is correct.
d) (A) is wrong but R is correct.
Answer:
b) Both (A) and (R) are correct, R does not explain A.
Correct Reason (R) : The phenoxide ion is more stabilised by resonance than phenol.

Question 4.
Assertion (A): Orthonitro phenol is slightly soluble in water and more volatile whereas p – nitro phenol is more soluble in water and less volatile.
Reason (R) : Orthonitro phenol forms intramolecular hydrogen bonding and p-nitro phenol forms intermolecular hydrogen bonding.
a) Both (A) and (R) are correct, R explains A.
b) Both (A) and (R) are correct, R does not explain A.
c) (A) is correct but R is correct.
d) (A) is wrong but R is correct.
Answer:
a) Both (A) and (R) are correct, R explains A.

III. Pick out the correct statements

Question 1.
(i) The structure of – OH group attached to a sp³– hybridised carbon in alcohol is similar to the structure of – OH group attached to a hydrogen in water.
(ii) Due to lone pair – lone pair repulsion, the – C – O – H bond angle in methanol is reduced to 104° from the regular tetrahedral bond angle of 109.5°.
(iii) With Grignard reagent formaldehyde gives primary alcohol and other aldehydes give secondary alcohols.
(iv) Reaction of Grignard reagent with aldehydes and ketones to form alcohols is an example for nucleophilic substitution reaction.
a) (i) & (ii)
b) (ii) & (iii)
c) (i) & (iii)
d) (i) & (iv)
Answer:
c) (i) & (iii)
Correct statements : (ii) Due to lone pair – lone pair repulsion, the – C – O – H bond anlge in methanol is reduced to 108.9° from the regular tetrahedral bond angle of 109.5°.
(iv) Reaction of Grignard reagent with adlehydes and ketones to form alcohols is an example for nucleophilic addition reaction.

Question 2.
(i) Lower alcohols are waxy solids and the higher members are colourless liquids.
(ii) Due to the presence of intermolecular hydrogen bonding alcohols have higher boiling point than the corresponding alkanes, aldehydes, ethers etc.
(iii) Due to the formation of intermolecular hydrogen bonding with water lower alcohols are highly soluble in water.
(iv) Among isomeric alcohols primary alcohols have lower boiling point and tertiary alcohols have higher boiling points.
a) (i) & (ii)
b) (ii) & (iii)
c) (iii) & (iv)
d) (i) & (iv)
Answer:
b) (ii) & (iii)
Correct statements : (i) Lower alcohols are colourless liquids and the higher members are waxy solids.
(iv) Among isomeric alcohols primary alcohols have higher boiling point and the tertiary alcohols have lower boiling points.

Question 3.
(i) In Swern Oxidation DMSO, oxalyl chloride and triethylamine are used to convert alcohols into aldehydes / ketones.
(ii) Vapours of primary alcohol passed over heated copper at 573 K undergoes dehydration. .
(iii) Methanol reacts with ethanoic acid in presence of an acid to form ethylethanoate.
(iv) Vapours of tertiary alcohols react with heated copper at 573 K to give alkenes.
a) (i) & (ii)
b) (ii) & (iii)
c) (iii) & (iv)
d) (i) & (iv)
Answer:
d) (i) & (iv)
Correct statements : (ii) Vapours of primary alcohol passed over heated copper at 573 K undergoes dehydrogenation.
(iii) Methanol reacts with ethanoic acid in presence of an acid to form methyl ethanoate. (or)
Ethanol reacts with ethanoic acid in presence of an acid to form ethyl ethanoate.

Question 4.
(i) Glycerol contains two primary alcoholic group and one secondry alcoholic group.
(ii) Oxidation of glycerol with cone. HNO₃ gives mainly formic acid.
(iii) Glycerol is used in making printing inks, and stamp pad ink.
(iv) Glycerol is used as a preservative for biological specimens
a) (i) & (ii)
b) (ii) & (iii)
c) (i) & (iii)
d) (i) & (iv)
Answer:
c) (i) & (iii)
Correct statements : (ii) Oxidation of glycerol with cone. HNO3 gives mainly glyceric acid
(iii) Ethanol is used as a preservative for biological specimens

IV. Pick out the incorrect statements

Question 1.
(i) The overall reaction of hydroboration is hydration of an alkene.
(ii) Hydroboration reaction occurs according to Markownikoff’s rule.
(iii) Raney Ni does not reduce the Carbon – Carbon double bond present in the Carbonyl compound to form unsaturated alcohols.
(iv) When two or more functional groups are present in a molecule sodium borohydride to used as a reducing agent to reduce the more reactive group
a) (i) & (ii)
b) (ii) & (iii)
c) (iii) & (iv)
d) (i) & (iv)
Answer:
b) (ii) & (iii)
Correct statements : (ii) Hydroboration reaction occurs against Markownikoff’s rule.
(iii) Lithium aluminium hydride does not reduce the Carbon – Carbon double bond present in the Carbonyl compound to form unsaturated alchols.

Question 2.
(i) Ethanol forms a turbidity with Lucas reagent within 10 minutes.
(ii) 2 – Methyl propan – 2 – ol forms immediate turbidity with Lucas reagent due to the formation of insoluble 2 – chloro – 2 – methyl propane.
(iii) Ehanol forms red colour in Victor Meyer’s test.
(iv) 2 – 2 – dimethyl propan – 1 – ol gives a colourless solution in victor Meyer’s test,
a) (i) & (ii)
b) (ii) & (iii)
c) (iii) & (iv)
d) (i) & (iv)
Answer:
d) (i) & (iv)
Correct statements : (i) Ethanol forms no tubridity with lucas reagent at room temperature.
(iv) 2,2 – dimethyl propan -1 – ol gives red colour in victor mayer’s test.

Question 3.
(i) Alcohols undergo nucleophilic substitution reaction with hydrohaloacids to form alkyl halides.
(ii) Alkyl halide formation from primary alchols follow E2 mechanism.
(iii) Alkyl halide formation from tertiary alcohols follow SN2 mechanism.
(iv) The conversion of methanol into chloromethane with thionyl chloride in the presence of pyridine follows SN2 mechanism.
a) (i) & (ii)
b) (ii) & (iii)
c) (iii) & (iv)
d) (i) & (iv)
Answer:
b) (ii) & (iii)
Correct statements : (ii) Alkyl halide formation from primary alcohols follow \(\mathrm{S}_{\mathrm{N}}^{2}\) mechanism.
(iii) Alkyl halide formation from tertiary alcohols follow \(\mathrm{S}_{\mathrm{N}}^{1}\) mechanism.

Question 4.
(i) In phenol the carbon bearing the – OH group is sp2 hybridised.
(ii) Unlike alcohols phenol reactswith sodium hydroxide to form sodium phenoxide.
(iii) In substituted phenols, the electron with drawing groups decreases the acidic nature of phenol.
(iv) Alkyl substituted phenols show increased acidity due to electron releasing +1 effect of alkvl group.
a) (i) & (ii)
b) (ii) & (iii)
c) (iii) & (iv)
d) (i) & (iv)
Answer:
c) (iii) & (iv)
Correct statements: (iii) In substituted phenols, the electron withdrawing groups increases the acidic
nature of phenol.
(iv) Alkyl substituted phenols show a decreased acidity due to electron releasing + I effect of alkyl
group.

V. Match the Following

Question 1.

Answer:
i) d glyceric acid & tartronic acid
ii) e glyceric acid
iii) a meso oxalic acid
iv) f glycerose
v) b formaldehyde & formic acid
vi) c oxalic acid

Question 2.

Answer:
i) d Substituted phenol
ii) c Dihydric phenol
iii) a Monohydric phenol
iv) b Trihydric phenol

Question 3.

Answer:
i) c Carbolic soaps
ii) e Cordite
iii) a Antifreeze
iv) b Perfumery
v) d Refrigerant

Question 4.

Answer:
i) e Neo pentyl alcohol
ii) d Isopropyl alcohol
iii) f 2-phenyl propan-2-ol
iv) c Ethylene glycol
v) a Glycerol
vi) b Sorbitol

VI. Two Marks Questions

Question 1.
Illustrate Markownikoff’s rule in the addition of water to an alkene
Answer:
Markownikoff’s rule states that the negative part of the adding molecules gets attached with the carbon containing least number of hydrogen atoms across the double bond.

Question 2.
Write a note on hydroboration reaction
Answer:
Diborane reacts with an alkene to form trialkyl borane which on treatment with H2O2 in presence of NaOH gives an alcohol.
The overall reaction is hydration of an alkene.
This reaction gives an anti MarkowniKoff’s product

Question 3.
Convert crotonaldehyde into crotylalcohol
Answer:
LiAlH₄ does not reduce C = C bond present in the carbonyl compound.
Hence it is the best reagent to prepare unsaturated alcohols.

Question 4.
An organic compound (A) – C₃H₈O₃ used as sweetening agent, which on oxidation with Fenton’s reagent gives a mixture of compounds B and C. Identify A, B & C. Write possible reactions.
Answer:
An organic compound (A) – C₃H₈O₃ is glycerol.
Oxidation of glycerol with Br₂/H₂O (or) NiaOBr (or) Fenton’s reagent (FeSO₄ + H₂O₂) gives a mixture of glyceraldehvde and dihydroxv acetone ( This mixture is named as glvcerose)

Question 5.
What is saponification?
Answer:
The alkaline hydroysis of naturally occurring oils and fats into glycerol and soap is called saponification.

Question 6.
What is Saytzeff’s rule
Answer:
During intramolecular dehydration of an alcohol if there is a possibility to form a carbon- carbon double bond at different locations, the preferred location is the one that gives the more substituted alkene ie., the stable alkene.

Question 7.
Convert propan -1 – ol to propanal.
Answer:
To stop the oxidation reaction of alcohols at the aldehyde / ketone stage, pyridinium chloro chromate (PCC) is used as an oxidising agent.

Question 8.
Write a note on Swern Oxidation
Answer:
In Swern oxidation dimethvl sulfoxide (DMSO) is used as the oxidising agent.
It converts alcohols to ketones / aldehydes.
Alcohol is treated with DMSO and oxah I chloride followed by the addition of triethylarnine.

Question 9.
Write note on biological oxidation that occurs in animals.
Answer:

• The fermentation of the food consumed by an animal produces alcohol.
• To detoxify the alcohol, liver produces an enzyme called alcohol dehydrogenase (ADH)
• Nicotinamide adenine dinucleotide (NAD) present in animals acts as an oxidising agent.
• ADH catalyses the oxidation of toxic alcohols into non-toxic aldehyde.

Question 10.
What happens when ethylene glycol is reacted with PI₃ ?
Answer:

Question 11.
What happens when ethylene glycol is heated with conc. HNO₃ and conc. H₂SO₄?
Answer:

Question 12.
How is nitroglycerine prepared
Answer:
Glycerol reacts with nitric acid in the presence of cone. H₂SO₄ to form nitroglycerine (TNG)

Question 13.
Write about the dehydration of glycerol
Answer:
When glycerol is heated with dehydrating agents such as H₂SO₄, KHSO₄ etc., it undergoes dehvration to form acrolein.

Question 14.
Convert aniline into phenol
Answer:

Question 15.
What is Schotten – Baumann reaction
Answer:
Benzovlation of phenol with benzoyl chloride in presence of NaOH is known as Schotten Baumann reaction.

Question 16.
Write a note on williamson ether synthesis?
Answer:
Methyl iodide undergoes nucleophilic substitution by phenoxide ion to form anisole

Question 17.
Convert phenol into (i) 1, 4 – benzoquionone (ii) cyclo hexanol
Answer:

Question 18.
How is picric acid prepared?
Answer:
Phenol undergoes nitration with cone HNO₃ and cone H₂SO₄ at 298 K to form 2, 4/ 6 – trinitrophenol known as picric acid

Question 19.
Differentiate phenol and ethanol
Answer:

Question 20.
Give four uses or diethyl ether.
Answer:

1. Diethyl ether is used as a surgical anaesthetic agent in surgery.
2. It is a good solvent for organic reactions and extraction.
3. It is used as a volatile starting fluid for diesel and gasoline engine.
4. It is used as a refrigerant.

Question 21.
Write the mechanism of intermolecular dehydration of alcohols?
Answer:

Question 22.
Write the mechanism of nucleophilic substitution of ethers
Answer:
Mechanism:
Ethers having primary alkyl group undergo SN2 reaction while tertiary alkyl ether undergo SN1 reaction.Protonation of ether is followed by the attack of halide ion.The halide ion preferentially attacks the less sterically hindered of the two alkyl groups which are attached to etherial oxygen.

When excess HBr or HI is used, the alcohol formed will further react with HBr or HI to form alkyl halides.

Question 23.
What is autooxidation of ethers?
Answer:

• Ethers stored in the presence of atmospheric oxygen slowly oxidise to form hydroperoxides and dialkyl peroxides.
• These are explosive in nature.
• This spontaneous oxidation by atmospheric oxygen is called auto oxidation

Question 24.

Answer:

Question 25.
Complete the reaction

Answer:

The bond of oxygen with phenyl ring is strong, hence it can not be broken and iodo benzene is not formed.

VII. Three Mark Questions

Question 1.
Explain the structure of the functional group of alcohol
Answer:

• The structure of – O – H group attached to a SP³ hybridised carbon is similar to the structure of – O – H group attached to a hydrogen in water, ie., ‘V! shaped.
• In such alcohols, one of the sp³ hybridised orbital of oxygen linearly overlap with the sp3 hybridised orbital of carbon to form a C – O, ‘σ’ bond.
• Another SP3 hybridised orbital linearly overlap with IS orbital of hydrogen to form a O-H, a’ bond.
• Remaining two sp3 hybridized orbitals of oxygen are occupied by two lone pairs of electrons.
• Due to lone pair – lone pair repulsion, the C – O – H bond angle in methanol is reduced to 108.9C from the regular tetrahedral bond angle of 109.5°.

Question 2.
Convert acetaldehyde into crotyl alc0hol
Answer:

LiAlH₄ selectively reduces the carbonyl group leaving the C = C bond.

Question 3.
Explain Lucas test of differentiating three types of alcohols
Answer:

The alkyl chloride formed in this reaction is insoluble in water, hence it appears as turbidity.

Question 4.
Write a note on catalytic dehydrogenation of three types of alcohols.
Answer:
Catalytic dehydrogenation :
When the vapours of a primary or a secondary alcohol are passed over heated copper at 573K, dehydrogenation takes place to form aldehyde or ketone.

Question 5.
Write about the oxidation of ethylene glycol
Oxidation of glycol
Answer:
On oxidation, glycol gives a variety of products depending on the nature of oxidizing agent and
other reaction conditions.
i) When nitric acid (or) alkaline potassium permanganate is used as the oxidizing agent, the following products are obtained.

ii) Oxidation of glycol with periodic acid :
Ethylene glycol on treatment with periodic acid gives formaldehyde. This reaction is selective for vicinal 1,2 – diols and it proceeds through a cyclic periodate ester intermediate.

Question 6.
Why is C-O-C bond angle in ether slightly greater than the tetrahedral bond angle.
Answer:

• Structure of ethereal oxygen attached to two alkyl groups is similar to the structure of – O – H group of alcohol.
• Oxygen atom is sp³ hybridised.
• Two sp3 hybridised orbitals of oxygen linearly overlap with two sp³ hybrid orbitals of the two carbon atoms attached directly to the oxygen forming two C – O ‘o ‘ bonds.
• C-O-C bond angle is slightly greater than the tetrahedral bond angle due to the repulsive interaction between the two bulkier alkyl group.

Question 7.
For the preparation of mixed ether having primary and tertiary alkyl group, primary alkyl halide and alkoxide are used. Why?
Answer:
Primary alkyl halides are more susceptible for SN2 reaction.
Hence for the preparation of mixed ether having primary and tertiary alkyl group, primary alkyl halide

On the other hand, if tertiary’ alkyl halide and primary alkoxide are used elimination reaction dominates and succeeds over substitution reaction to form an alkene.

Question 8.
How do you convert anisole into (i) Methoxy toluene (ii) methoxy acetophenone
Answer:

Question 9.
375 mg of an alcohol reacts with required amount of methyl magnesium bromide and releases 140 mL of methane gas at STP. What is the formula of the alcohol?
Solution:

(1 mole) 22,400 mL of methane can be produced from 1 mole of alcohol.
140 ml of methane is liberated from 1/22400 x 140 mole of alcohol = 6.25 x 10^-3 mole of alcohol
w = 375 mg = 375 x 10^-3 g; n = 6.25 x 10^-3

Molar mass of alcohol is 60 gmol^-1
CnH2n+1 -OH=>nxl2 + (2n + 1)xl + lxi6+1xl=60
12n + 2n + 1 + 16 + 1 = 60 14n + 18 = 60
14n = 60 – 18
Hence the formula of the alcohol is C₃H₇OH .
n = 42/14 ⇒ n = 3

Question 10.
How will you convert methanol into ethanol?
Answer:

VIII. Five Mark Questions

Question 1.
Convert methyl magnesium iodide into
(i) ethanol
(ii) propan – 2 – ol
(iii) 2 – methyl propan – 2 – ol
Answer:

Question 2.
Bring about the following conversion using Grignard reagents
i) Methanal into phenyl methanol
ii) Ethanal into butan – 2 – ol
iii) Propanone into 2 – methyl hexan – 2 -ol
iv) Ethyl methanoate into propan – 2 – ol
v) Formaldehyde into propan-l-ol
Answer:

Question 3.
A ether (A) C₅H₁₂O when heated with excess of hot concentration HI, produced two alkyl halides, which on hydrolysis forms compound (B) and (C). Oxidation of (B) gives an acid (D) where as oxidation of (C) gives ketone (E). Identify A, B, C, D and E and write the chemical equation.
Answer:
A ether (A) C₅H₁₂O when heated with excess of hot concentration HI, produced two alkyl halides.

Question 4.
Explain E₁mechanism involved in the dehydration of tertiary butyl alcohol
Answer:
Tertiary alcohols undergo dehydration by E₁ mechanism. It involves the formation of a carbocation.
Protonation of alcohol

Question 5.
An organic compound C₂H₆O (A) heated with Cone. H₂SO₄ at 443K to give and unsaturated hydrocarbon C₂H₄ (B), which on treatment with Baeyer’s reagent to give compound C₂H₆O₂ (C). Which is used as antifreeze in automobile radiator. Compound (C) distilled with cone. H₂SO₄ to give cyclic compound (C₄H₈O₂) (D). Compound (A) is heated with cone H₂SO₄ at 413K to give compound C₄H₁₀O (E). Identify compounds (A) to (E) and write equations Compound (A) is Ethanol heated with Cone. H₂SO₄ at 443K to give compound (B) is Ethene
Answer:

Compound (B) on treatment with Baeyer’s reagent to give compound (C) is Ethylene glycol

Compound ( C) distilled with cone. H₂SO₄ to give cyclic compound (D) 1,4- dioxene

Compound (A) is heated with cone. H₂SO₄ at 413K to give compound (E) is diethylether

Question 6.
Explain the oxidation of glycerol
Answer:

Question 7.
Write a note on (i) Riemer Tiemann reaction (ii) Phthalein reaction (iii) coupling reaction
Answer:
i) Riemer Tiemann Reaction:
On treating phenol with CHCl₃ /NaOH, a -CHO group is introduced at ortho position This reaction proceeds through the formation of substituted benzal chloride intermediate.

(ii) Phthalein reaction:
On heating phenol with phthalic anhydride in presence of con.H₂SO₄ phenolphthalein is obtained.

iii) Coupling reaction:
Phenol couples with benzene diazonium chloride in an alkaline solution to form p-hydroxy azobenzene (a red-orange dye).

Question 8.
Write any three methods of preparing ethers
Answer:
(i) Intermolecular dehydration of alcohol
Ethanol undergoes intermolecular dehydration with conc. H₂SO₄ at 413 K to form diethyl ether. Conc. H₂SO₄

(ii) Williamson ether synthesis
When an alkyl halide is heated with an alcoholic solution of sodium alkoxide, the corresponding ether is obtained. This involves SN² mechanism.

(iii) Methylation of alcohol
Methyl ethers can be prepared by treating alcohol with diazomethane in presence of catalyst fluoroboric acid

Question 9.
How does diethylether react with the following
(i) Cl₂/light
(ii) PCl₅
(iii) dilH₂SO₄
(iv) CH₃COCl/anhy.ZnCl₂
Answer:

Question 10.
Convert
(i) methanol into tertiary butyl alcohol
(ii) ethanol into 1- butanol
Answer:

Question 11.
Complete the reaction

Answer:

(y) Reduction to pinacols: Ketones, on reduction with magnesium amalgam and water, are reduced to symmetrical diols known as pinacol.

Tamilnadu State Board New Syllabus Samacheer Kalvi 12th Business Maths Guide Pdf Chapter 2 Integral Calculus I Ex 2.1 Text Book Back Questions and Answers, Notes.

Tamilnadu Samacheer Kalvi 12th Business Maths Solutions Chapter 2 Integral Calculus I Ex 2.1

Question 1.
Integrate the following with respect to x.
\(\sqrt { 3x+5 }\)
Solution:

Question 2.
(9x² – \(\frac { 4 }{x^2}\))²
Solution:
A = \( \left[\begin{array}{cccc}
-2 & 1 & 3 & 4 \\
0 & 1 & 1 & 2 \\
1 & 3 & 4 & 7
\end{array}\right]\)
The order of A is 3 × 4
∴ P(A) < 3
Let us transform the matrix A to an echelon form

The number of non-zero rows = 3
∴ P(A) = 3

Question 3.
(3 + x) (2 – 5x)
Solution:
∫(3 + x) (2 – 5x) dx
= ∫(6 – 15x + 2x – 5x²) dx
= ∫(6 – 13x – 5x²) dx
= 6x – \(\frac { 13x^2 }{2}\) – \(\frac { 5x^3 }{3}\) + c

Question 4.
√x (x³ – 2x + 3)
Solution:

Question 5.
\(\frac { 8x+13 }{\sqrt{4x+7}}\)
Solution:

Question 6.
\(\frac { 1 }{\sqrt{x+1}+\sqrt{x-1}}\)
Solution:

Question 7.
Given f'(x) = x + b, f(1) = 5 and f(2) = 13, then find f(x)
Solution:
f(x) = ∫f'(x) dx
f(x) = ∫(x + b) dx = \(\frac { x^2 }{2}\) + bx + c
f (1) = 5 ⇒ \(\frac { (1)^2 }{2}\) + b(1) + c = 5
\(\frac { 1 }{2}\) + b + c = 5 ⇒ b + c = 5 – 1/2
b + c = \(\frac { 9 }{2}\) ⇒ 2b + 2c = 9 …….. (1)
f(2) = 13 ⇒ \(\frac { (2)^2 }{2}\) + b(2) + c = 13
2 + 2b + c = 13
2b + c = 11 ……… (2)
Solving eqn (1) & (2)

Substitute c = -2 in eqn (2)
2b – 2 = 11 ⇒ 2b = 11 + 2
b = 13/2
f(x) = \(\frac { x^2 }{2}\) + \(\frac { 13x }{2}\) – 2

Question 8.
Given f'(x) = 8x³ – 2x and f (2) = 8, then find f(x)
Solution:
f(x) = ∫f'(x)dx
= ∫(8x³ – 2x)dx = 8(\(\frac { x^4 }{4}\)) -2(\(\frac { x^2 }{2}\)) + c
f(x) = 2x⁴ – x² + c
f (2) = 8 ⇒ 2(2)⁴ – (2)² + c = 8
32 – 4 + c = 8 ⇒ c = -20
∴ f (x) = 2x⁴ – x² – 20

Tamilnadu State Board New Syllabus Samacheer Kalvi 12th Business Maths Guide Pdf Chapter 1 Applications of Matrices and Determinants Miscellaneous Problems Text Book Back Questions and Answers, Notes.

Tamilnadu Samacheer Kalvi 12th Business Maths Solutions Chapter 1 Applications of Matrices and Determinants Miscellaneous Problems

Question 1.
Find the rank of the matrix
A = \(\left(\begin{array}{cccc}
1 & -3 & 4 & 7 \\
9 & 1 & 2 & 0
\end{array}\right)\)
Solution:
\(\left(\begin{array}{cccc}
1 & -3 & 4 & 7 \\
9 & 1 & 2 & 0
\end{array}\right)\)
The order of A is 2 × 4
∴ P(A) ≤ 2
Let us transform the matrix A to an echelon form

The number of non-zero rows is 2
∴ P(A) = 2

Question 2.
Find the rank of the matrix
A = \( \left[\begin{array}{cccc}
-2 & 1 & 3 & 4 \\
0 & 1 & 1 & 2 \\
1 & 3 & 4 & 7
\end{array}\right]\)
Solution:
A = \( \left[\begin{array}{cccc}
-2 & 1 & 3 & 4 \\
0 & 1 & 1 & 2 \\
1 & 3 & 4 & 7
\end{array}\right]\)
The order of A is 3 × 4
∴ P(A) < 3
Let us transform the matrix A to an echelon form

The number of non-zero rows = 3
∴ P(A) = 3

Question 3.
Find the rank of the matrix
A = \(\left[\begin{array}{llll}
4 & 5 & 2 & 2 \\
3 & 2 & 1 & 6 \\
4 & 4 & 8 & 0
\end{array}\right]\)
Solution:
A = \(\left[\begin{array}{llll}
4 & 5 & 2 & 2 \\
3 & 2 & 1 & 6 \\
4 & 4 & 8 & 0
\end{array}\right]\)
The order of A is 3 × 4
∴ p(A) < 3
Let us transform the matrix A to an echelon form


The last equivalent matrix is in the echelon form.
Number of non-zero rows = 3
∴ P(A) = 3

Question 4.
Examine the consistency of the system of equations;
x + y + z = 7, x + 2y + 3z = 18, y + 2z = 6
Solution:
x + y + z = 7
x + 2y + 3z = 18
y + 2z = 6
The matrix form of the equations

Here p(A) ≠ p(A, B)
∴ The given system is inconsistent and has no solution.

Question 5.
Find k if the equations 2x + 3y – z = 5, 3x – y + 4z = 2, x + 7y – 6z = k are consistent.
Solution:
2x + 3y – z = 5
3x – y + 4z = 2
x + 7y – 6z = k
The matrix form of these equations

Obviously, the last equivalent matrix is in the ech-elon form.
Since the equations are consistent
P(-A) = p(A, B)
p(A) = 2 and p (A, B) = 2 then
k = 8

Question 6.
Find k if the equations x + y + z = 1, 3x – y – z = 4, x + 5y + 5z = k are inconsistent.
Solution:
x + y + z = 1
3x – y – z = 4
x + 5y + 5z = k
The matrix equation corresponding to the given system is

Obviously, the last equivalent matrix is in the ech-elon form.
Since the equations are inconsistent
p(A) ≠ p (A, B)
Here p(A) = 2 but p(A, B) should not equal to 2
∴ k ≠ 0
The equations are inconsistent when k assume any real value other than 0.

Question 7.
Solve the equations x + 2y + z = 7, 2x – y + 2z = 4, x + y – 2z = -1 by using Cramer’s rule.
Solution:
x + 2y + z = 7
2x – y + 2z = 4
x + y – 2z = -1
Here Δ = \(\left|\begin{array}{ccc}
1 & 2 & 1 \\
2 & -1 & 2 \\
1 & 1 & -2
\end{array}\right|\)
= 1(2 – 2)-2 (-4 – 2) + 1(2 + 1)
= 1(0) -2 (-6) + 1(3)
= 12 + 3 = 15 ≠ 0
∴ We can apply Cramer’s Rule and the system is consistent and it has unique solution.
Δ_x = \(\left|\begin{array}{ccc}
7 & 2 & 1 \\
4 & -1 & 2 \\
-1 & 1 & -2
\end{array}\right|\)
= 7 (2 – 2) -2 (-8 + 2) + 1(4 – 1)
= 7(0)-2 (-6) + 1(3)
= 12 + 3
= 15
Δ_y = \(\left|\begin{array}{ccc}
1 & 7 & 1 \\
2 & 4 & 2 \\
1 & -1 & -2
\end{array}\right|\)
= 1(-8 + 2) -7 (-4 – 2) + 1(-2 – 4)
= 1 (-6) – 7 (-6) + 1 (-6)
= -6 + 42 – 6 = 30
Δ_z = \(\left|\begin{array}{ccc}
1 & 2 & 7 \\
2 & -1 & 4 \\
1 & 1 & -1
\end{array}\right|\)
= 1(1 – 4) -2 (-2 – 4) + 7 (2 + 1)
= 1 (-3) -2 (-6) + 7 (3)
= -3 + 12 + 21 = 30
∴ By cramer’s rule

∴ The Solution is (x, y, z) = (1, 2, 2)

Question 8.
The cost of 2kg. of wheat and 1kg. of sugar is Rs 100. The cost of 3kg. of wheat, 2kg. of sugar and 1kg of rice is Rs 220. Find the cost of each per kg. using Cramer’s rule.
Solution:
Let cost of 1 kg of wheat be x; cost of 1kg of sugar be y and cost of 1 kg of rice be z.
2x + y = 100
x + z = 80
3x + 2y + z = 220
Here Δ = \(\left|\begin{array}{ccc}
2 & 1 & 0 \\
1 & 0 & 1 \\
3 & 2 & 1
\end{array}\right|\)
= 2 (0 – 2) -1 (1 – 3)
= – 4 + 2 = -2
≠ 0
∴ We can apply Cramer’s Rule and the system is consistent and it has unique solution.
Δ_x = \(\left|\begin{array}{ccc}
100 & 1 & 0 \\
80 & 0 & 1 \\
220 & 2 & 1
\end{array}\right|\)
= 100 (0 – 2) -1 (80 – 220)
= – 200 -1 (-140)
= – 200 +140
= -60
Δ_y = \(\left|\begin{array}{ccc}
2 & 100 & 0 \\
1 & 80 & 0 \\
3 & 220 & 1
\end{array}\right|\)
= 2 (80 – 220) -100 (1 – 3)
= 2 (-140) – 100 (-2)
= – 280 + 200
= -80
Δ_x = \(\left|\begin{array}{ccc}
2 & 1 & 100 \\
1 & 0 & 80 \\
3 & 2 & 220
\end{array}\right|\)
= 2 (0 -160) -1 (220 – 240) + 100 (2 – 0)
= 2 (-160) -1 (-20) + 100 (2)
= -320 + 20 + 200
= -100
∴ By cramer’s rule

The solution is (x, y, z) = (30, 40, 50)
∴ The cost of 1 kg of wheat is Rs 30; the cost of 1 kg of sugar is Rs 40 and the cost of 1 kg of rice is Rs 50.

Question 9.
A salesman has the following record of sales during three items A, B, and C, which has different rates of commission.

Find out the rate of commission on items A, B, and C by using Cramer’s rule.
Solution:
Let x, y, and z be the commission on items A, B, and C respectively.
90x + 100y + 20z = 800 ⇒ 9x + 10y + 2z = 80 ……… (1)
130x + 50y + 40z = 900 ⇒ 13x + 5y + 4z = 90 ………. (2)
60x + 100y + 30z = 850 ⇒ 6x + 10y + 3z = 85 ………. (3)
Here Δ = \(\left|\begin{array}{ccc}
9 & 10 & 2 \\
13 & 5 & 4 \\
6 & 10 & 3
\end{array}\right|\)
= 9 (15 – 40) -10 (39 – 24) + 2 (130 – 30)
= 9 (-25) – 10 (15) + 2 (100)
= -225 – 150 + 200
= -175
≠ 0
∴ We can apply Cramer’s Rule and the system is consistent and it has unique solution.
Δ_x = \(\left|\begin{array}{ccc}
80 & 10 & 2 \\
90 & 5 & 4 \\
85 & 10 & 3
\end{array}\right|\)
= 80 (15 – 40) -10 (270 – 340) + 2 (900 – 425)
= 80 (-25) -10 (-70) + 2 (475)
= -2000 + 700 + 950
= -350
Δ_y = \(\left|\begin{array}{ccc}
9 & 80 & 2 \\
13 & 90 & 4 \\
6 & 85 & 3
\end{array}\right|\)
= 9 (270 – 340) – 80 (39 – 24) + 2 (1105 – 540)
= 9 (-70)-80 (15) + 2 (565)
= -630 – 1200 + 1130
= -700
Δ_z = \(\left|\begin{array}{ccc}
9 & 10 & 80 \\
13 & 5 & 90 \\
6 & 10 & 85
\end{array}\right|\)
= 9 (425 – 900) -10 (1105 – 540) + 80 (130 – 30)
= 9 (-475) -10 (565) + 80 (100)
= – 4275 – 5650 + 8000
= -1925
∴ By cramer’s rule

The solution is (x, y, z) = (2, 4, 11)
∴ The rates of commission for A, B and C are Rs 2, Rs 4 and Rs 11 respectively.

Question 10.
The subscription department of a magazine sends out a letter to a large mailing list inviting subscriptions for the magazine. Some of the people receiving this letter already subscribe to the magazine while others do not. From this mailing list, 60% of those who already subscribe will subscribe again while 25% of those who do not now subscribe will subscribe. In the last letter, it was found that 40% of those receiving it ordered a subscription. What percent of those receiving the current letter can be expected to order a subscription?
Solution:
The transition probability matrix is S

∴ 39% of those receiving the current letter can be expected to order a subscription.

Tamilnadu State Board New Syllabus Samacheer Kalvi 12th Commerce Guide Pdf Chapter 15 Recent Trends in Marketing Text Book Back Questions and Answers, Notes.

Tamilnadu Samacheer Kalvi 12th Commerce Solutions 15 Recent Trends in Marketing

12th Commerce Guide Recent Trends in Marketing Mix Text Book Back Questions and Answers

I. Choose The Correct Answer.

Question 1.
Selling goods/ services through internet is
a) Green marketing
b) E- business
c) Social marketing
d) Meta marketing
Answer:
b) E-business

Question 2.
Which is gateway to internet?
a) Portal
b) CPU
c) Modem
d) Webnaire
Answer:
c) Modem

Question 3.
Social marketing deals with:
a) Society
b) Social Class
c) Social change
d) Social evil
Answer :
c) Social change

Question 4.
Effective use of Social media marketing increase conversion rates of –
a) Customer to buyers
b) Retailer to customers
c) One buyer to another buyers
d) Direct contact of marketer
Answer:
a) Customer to buyers

Question 5.
A company’s products and prices are visually represented by
a) Shopping cart
b) Web portal
c) Electronic catalogue
d) Revenue model
Answer:
c) Electronic catalogue

Question 6.
Pure play retailers are called
a) Market creators
b) Transaction brokers
c) Merchants
d) Agents
Answer:
b) Transaction brokers

II. Very Short Answer Questions.

Question 1.
What is E-Business?
Answer:
If all the business transactions are carried out through the internet and other online tools, it is called E-business.

Question 2.
What is green marketing?
Answer:

• It refers to a holistic marketing concept with growing awareness about the implications of Global warming, non -biodegradable solid waste, the harmful impact of pollutants, etc.
• It is also known as “Environmental marketing”, “Ecological marketing” Eco-friendly marketing and sustainable marketing”.

Question 3.
What is service marketing?
Answer:
Service marketing denotes the processing of selling service goods like telecommunication, banking, insurance, car rentals, healthcare, tourism, professional services, repairs etc.

Question 4.
Define E-Marketing.
Answer:
“E-Marketing refers to the application of a broad range of information technology for creating more customer value through more effective segmentation, targeting differentiation and positioning strategies, planning more efficiently and executing the conception distribution, promotion and pricing of goods, services and ideas and creating exchanges that satisfy individual consumer and organization’s consumer objectives”. _ JUDY STRAUSS

Question 5.
What is E-Tailing?
Answer:
E-tailing or electronic retailing refers to the selling of goods and services through a shopping website (internet) or through a virtual Store to the ultimate consumer.

Question 6.
What is social marketing?
Answer:

• Social marketing is a new marketing tool
• It is the systematic application of marketing philosophy and techniques to achieve specific behavioural goals that ensure social good
• [Eg] Asking people- Not to smoke in a public place.

III. Short Answer Questions.

Question 1.
What are the advantages of E-Marketing?
Answer:

• Any time market: E-Marketing provides 24 hours and 7 days “24/7” Service to its users. So consumer can shop or order the product anytime from anywhere.
• Direct contact of end consumer by the manufacturer cuts down the substantially intermediation cost. Thus products bought through e-marketing become cheaper.
• Customers can buy whatever they want / need just by browsing the various sites.

Question 2.
Discuss the objectives E-Marketing (EARS)
Answer:

• Expansion of market share.
• Achieving higher brand awareness.
• Reduction of distribution and promotional expenses
• Strengthening database.

Question 3.
Explain in detail Niche marketing. [Nitch] [Neesh]
Answer:

• “Niche marketing “ denotes a strategy of directing all marketing efforts towards one well-defined segment of the population.
•  Actually, there is no market in a niche market.
•  It is found by the company, by identifying the need of customers who are not served or underserved by the competitors.
• It involves a specific target audience with a specialized offering.
•  It aimed at being a big fish in a small pond instead of being a small fish in a big pond.
•  [eg] Not everybody wants to watch the movie by paying 5x-6xtimes the cost of the normal tick.

IV. Long Answer Questions.

Question 1.
Explain in detail how traditional marketing differ from E-marketing [FEETS].
Answer:

Question 2.
Explain the advantages and disadvantages of E-marketing.
Answer:
E-tailing or electronic retailing refers to the selling of goods and services through a shopping website:
Advantages:

1. Customer can buy the product at any time from anywhere.
2. Direct contact of end consumer by the manufacturer cuts down the cost.
3. Customer can buy whatever they want by browsing the various sites.

Disadvantages:

1. E-tailing needs a strong advertisement and for which it has to spend large amount.
2. It is not suitable for small size business.

Question 3.
Discuss any two new methods of marketing with their advantages.
Answer:|
1. Rural Marketing:
Rural marketing is a process of developing pricing, promoting, and distributing rural specific goods and services leading to exchange with rural customers. There is an inflow of goods into rural markets for production and consumption and there is also an outflow of products to urban areas. the rural to urban flow consists of agricultural products like rice, wheat and sugar, etc.

2. Service Marketing:
Service marketing is a special branch of marketing. It denotes the processing of selling service goods like telecommunication, banking, insurance, healthcare, tourism, and professional services. The service products are mostly intangible. The unique feature of services marketing warrants different strategies compared with the marketing of physical goods.

12th Commerce Guide Recent Trends in Marketing Additional Important Questions and Answers

I. Choose The Correct Answer.

Question 1.
Pick the odd one out:
a) E-Commerce
b) E-Marketing
c) E-Tailing
d) E-Banking
Answer:
d) E-Banking

Question 2.
Find out which is not suitable? The products marketed in commodity exchange are ______
(a) Crude oil
(b) Rice
(c) Copper
(d) Gold
Answer:
(b) Rice

Question 3.
…………… is marketing knowns as environmental marketing or Ecological marketing or Eco-friendly marketing or sustainable marketing
a) Green
b) Social
c) Service
d) Rural
Answer:
a) Green

Question 4.
…………….. Marketing is holistic with growing awareness about implications of Global warming Non-Bio degradable solid waste harmful impact of pollutants etc.
a) Rural
b) Traditional
c) Service
d) Green
Answer:
d) Green

Question 5.
Which one of the following is not correctly matched?
a) Referral marketing – Reference
b) Content marketing – Communicating
c) E-Tailing – Online
d) Service marketing – Anti-drug
Answer:
d) Service marketing – Anti-drug

Question 6.
Select the odd one out.
a) Electronic marketing
b) Online marketing
c) Web marketing
d) Traditional marketing
Answer:
d) Traditional Marketing

Question 7.
Which one represents a cluster of manufacturers, content providers and online retailers organised around an activity?
a) Virtual mall
b) Association
c) Metomediary
d) Portal
Answer:
c) Metomediary

Question 8.
Green Shelter concept was introduced by group:
a) ACME
b) Tata
c) Reliance
d) ICI
Answer:
a) ACME

II. Match The Following

1. Match list -1 with list 2

Answer:
a) (i) 4, (ii) 3, (iii) 1, (iv) 2

Question 2.

Answer:
c) (i) 2,(ii) 3,(iii) 1,(iv) 4

Question 3.

Answer:
a) (i) 4, (ii) 3, (iii) 2, (iv) 1

III. Assertion and Reason

Question 1.
Assertion [ A] : Actually there is no market in niche market
Reason [B]: It is found by identifying the need of customers which are not served and under served by the competitions .
a) A is true R is false
b) A is false R is true
c) A and R are true
d) A and R are false
Answer:
c) A and R are true

Question 2.
Assertion [A]: “Offer more – for less “ is a strategy to satisfy the consumers
Reason [R ]: They use computers, laptops tablets smart-phone android phone to access different websites.
a. A is true R is false
b. A and R are true
c. A and R are false
d. A and R are false
Answer:
b) A and R are true

IV. Short Answer Questions.

Question 1.
What is B2B and B2C type of E-Commerce?
Answer:
B2B-Business to Business:

• Under this model .Business concerns transact with one another through internet.
• [eg] Flipkart

B2C- Business to consumer:

• Under this model Business concerns sell directly to the consumers.
• [eg] Shopping zone .

Question 2.
Explain the importance of social marketing ?
Answer:

• It helps to eradicate social evils that affect the society and quality of life
• It promotes the consumption of socially desirable products and develops health consciousness.
• It is a new marketing tool by using philosophy and techniques to achieve specific behavioural goals which ensure social goal.

Question 3.
Elucidate how E-Commerce differs from E-Business.
Answer:

• E-Commerce simply refers to the buying and selling of products and services through online.
• E-Business goes away beyond the simple buying and selling goods and services and much wider range of business processes.
• E-Commerce and E-Business is used interchangeably in its broader meaning just as trade and commerce.

V. Long Answer Questions.

Question 1.
Describe the various strategies pursued in recent day’s marketers.
Answer:
Viral Marketing:

• “Viral marketing “ is a marketing technique that impels the users to pass on a marketing message to other users, creating a potentially exponential in the message visibility and effect.
•  It is able to generate interest and potential sale of a brand or product through messages that
  spread quickly like a virus from person to person.
• [eg] Emergency needs through you tube, face book, twitter etc… [Need of blood -to save the life]

Guerrilla marketing:
“ Guerilla marketing “ represents an advertisement strategy to promote or services on streets or other public places with monkey like malls, parks, beach etc.

Referral marketing:
“Referral marketing is the method of promoting products or services to new customers through existing customers.

Ambush marketing:

• It is a new technique where by a particular advertiser seeks to connect his product to the event in the mind of polentional customers without paying sponsoring expenses to the event.
• [eg] X has sponsored a cricket match to promote his brand. A group of people sitting on the gallery wearing Y’ brand name T- shirts come in to focuses, in this case ‘Y’ promotes his brand at ‘X’ expense.

Multilevel marketing:

• It is the marketing strategy where in the direct sales companies encourage its existing distributors
• ID recruit new distributors to facilitate the sale of goods and services.

Content marketing:
It is said to be the art of communicating with customers and prospects without selling.

Question 2.
Compare the concept of social marketing with service marketing. (BEEP)
Answer:

Tamilnadu State Board New Syllabus Samacheer Kalvi 12th Business Maths Guide Pdf Chapter 1 Applications of Matrices and Determinants Ex 1.4 Text Book Back Questions and Answers, Notes.

Tamilnadu Samacheer Kalvi 12th Business Maths Solutions Chapter 1 Applications of Matrices and Determinants Ex 1.4

Choose the most suitable answer from the given four alternatives:

Question 1.
A = (1, 2, 3), then the rank of AA^T is
(a) 0
(b) 2
(c) 3
(d) 1
Solution:
(d) 1
Hint:
A = (1, 2, 3) then
A^T = \(\left(\begin{array}{l}
1 \\
2 \\
3
\end{array}\right)\)
AA^T = (1, 2, 3) \(\left(\begin{array}{l}
1 \\
2 \\
3
\end{array}\right)\) = (1 + 4 + 9) = (14)
Number of non-zero rows = 1
∴ P (AA^T) = 1

Question 2.
The rank of m × n matrix whose elements are unity is
(a) 0
(b) 1
(c) m
(d) n
Solution:
(b) 1

Question 3.
If T = is a transition probability matrix, then at equilibriuium A is equal to
(a) \(\frac { 1 }{ 4 }\)
(b) \(\frac { 1 }{ 5 }\)
(c) \(\frac { 1 }{ 6 }\)
(d) \(\frac { 1 }{ 8 }\)
Solution:
(a) \(\frac { 1 }{ 4 }\)
Hint:

At equilibrium (A B) \(\left(\begin{array}{ll}
0.4 & 0.6 \\
0.2 & 0.8
\end{array}\right)\)
0.4 A + 0.2 B = A
0.4 A + 0.2(1 – A) = A
0.4 A + 0.2 – 0.2 A = A
0.2 A + 0.2 = A
0.2 = A – 0.2 A
0.2 = 0.8 A
A = \(\frac { 0.2 }{ 0.8 }\) = \(\frac { 1 }{ 4 }\)

Question 4.
If A = \(\left(\begin{array}{ll}
2 & 0 \\
0 & 8
\end{array}\right)\), then p(A) is
(a) 0
(b) 1
(c) 2
(d) n
Solution:
(c) 2
Hint:
A = \(\left(\begin{array}{ll}
2 & 0 \\
0 & 8
\end{array}\right)\)
No. of Non-zero rows = 2
∴ p(A) = 2

Question 5.
The rank of the matrix \(\left[\begin{array}{lll}
1 & 1 & 1 \\
1 & 2 & 3 \\
1 & 4 & 9
\end{array}\right]\) is
(a) 0
(b) 1
(c) 2
(d) 3
Solution:
(d) 3
Hint:

No. of Non-zero rows = 3
∴ p(A) = 3

Question 6.
The rank of the unit matrix of order n is
(a) n – 1
(b) n
(c) n + 1
(d) n²
Solution:
(b) n

Question 7.
If p(A) = r then which of the following is correct?
(a) all the minors of order r which does not vanish
(b) A has at least one minor of order r which does not vanish
(c) A has at least one (r + 1) order minor which vanishes
(d) all (r + 1) and higher order minors should not vanish
Solution:
(b) A has at least one minor of order r which does not vanish.

Question 8.
If A = \(\left(\begin{array}{l}
1 \\
2 \\
3
\end{array}\right)\) then the rank of AA^T is
(a) 0
(b) 1
(c) 2
(d) 3
Solution:
(b) 1
Hint:

No. of non-zero rows = 1
p (AA^T) = 1

Question 9.
If the rank of the matrix \(\left[\begin{array}{ccc}
\lambda & -1 & 0 \\
0 & \lambda & -1 \\
-1 & 0 & \lambda
\end{array}\right]\) is 2. then λ is
(a) 1
(b) 2
(c) 3
(d) only real number
Solution:
(a) 1
Hint:
A = \(\left[\begin{array}{ccc}
\lambda & -1 & 0 \\
0 & \lambda & -1 \\
-1 & 0 & \lambda
\end{array}\right]\)
Since the Rank is 2, third order matrix vanishes
∴ |A| = 0
\(\left[\begin{array}{ccc}
\lambda & -1 & 0 \\
0 & \lambda & -1 \\
-1 & 0 & \lambda
\end{array}\right]\) = 0
λ(λ² – 0) + 1 (0 – 1) = 0
λ³ – 1 = 0 ⇒ λ³ = 1
∴ λ = 1

Question 10.

(a) 0
(b) 2
(c) 3
(d) 5
Solution:
(c) 3
Hint:
Number of non-zero rows = 3
∴ Rank = 3

Question 11.
If is a transition probability matrix, then the value of x is
(a) 0.2
(b) 0.3
(c) 0.4
(d) 0.7
Solution:
(c) 0.4
Hint:

is a transition probability matrix then 0.6 + x = 1
x = 1 – 0.6
x = 0.4

Question 12.
Which of the following is not an elementary transformation?
(a) R_i ↔ Rj
(b) R_i → 2R_i + 2Cj
(c) R_i → 2R_i + 4Rj
(d) C_i → C_i + 5Cj
Solution:
(b) R_i → 2R_i + 2Cj

Question 13.
If p(A) = p(A,B)= then the system is
(a) Consistent and has infinitely many solutions
(b) Consistent and has a unique solution
(c) inconsistent
(d) consistent
Solution:
(d) Consistent

Question 14.
If p(A) = p(A,B)= the number of unknowns, then the system is
(a) Consistent and has infinitely many solutions
(b) Consistent and has a unique solution
(c) inconsistent
(d) consistent
Solution:
(b) Consistent and has a unique solution

Question 15.
If p(A) ≠ p(A, B) =, then the system is
(a) Consistent and has infinitely many solutions
(b) Consistent and has a unique solution
(c) inconsistent
(d) consistent
Solution:
(c) inconsistent

Question 16.
In a transition probability matrix, all the entries are greater than or equal to
(a) 2
(b) 1
(c) 0
(d) 3
Solution:
(c) 0

Question 17.
If the number of variables in a non-homogeneous system AX = B is n, then the system possesses a unique solution only when
(a) p(A) = p(A, B) > n
(b) p(A) = p(A, B) = n
(c) p(A) = p(A, B) < n
(d) none of these
Solution:
(b) p(A) = p(A, B) = n

Question 18.
The system of equations 4x + 6y = 5, 6x + 9y = 7 has
(a) a unique solution
(b) no solution
(c) infinitely many solutions
(d) none of these
Solution:
(b) no solution
Hint:
The matrix form of the equations

p(A) ≠ p(A, B)
∴ The system is inconsistent.

Question 19.
For the system of equations x + 2y + 3z = 1, 2x + y – z = 3, 3x + 2y + k = 4
(a) there is only one solution
(b) there exists infinitely many solution
(c) there is no solution
(d) none of these
Solution:
(a) there is only one solution
Hint:
The matrix form of the equations

The last equivalent matrix in the echelon form
p(A) = p (A, B) = no. of unknowns
∴ The system is consistent.

Question 20.
If |A| ≠ 0, then A is
(a) non – singular matrix
(b) singular matrix
(c) zero matrix
(d) none of these
Solution:
(a) non-singular matrix

Question 21.
The system of linear equations x = y + z = 2, 2x + y – z = 3, 3x + 2y + k = 4 has unique solution, if k is not equal to
(a) 1
(b) 0
(c) 3
(d) 7
Solution:
(b) 0
Hint:
The matrix form of the equations

Since the system has unique solution.
P(A) = p(A, B) ≠ n
∴ K ≠ 0

Question 22.
Cramer’s rule is applicable only to get an unique solution when
(a) Δ_z ≠ 0
(b) Δ_x ≠ 0
(c) Δ ≠ 0
(d) Δ_y ≠ 0
Solution:
(c) Δ ≠ 0

Question 23.

Then (x, y) is

Solution:
(d) (\(\frac { -Δ_1 }{ Δ_2 }\), \(\frac { -Δ_1 }{ Δ_3 }\))

Question 24.
|A_{n × n}| = 3 |adj A| = 243 = (3)5 then the value n is
(a) 4
(b) 5
(c) 6
(d) 7
Solution:
(c) 6

Question 25.
Rank of a null matrix is
(a) 0
(b) -1
(c) ∞
(d) 1
Solution:
(a) 0

Tamilnadu State Board New Syllabus Samacheer Kalvi 12th Commerce Guide Pdf Chapter 14 Marketing and Marketing Mix Text Book Back Questions and Answers, Notes.

Tamilnadu Samacheer Kalvi 12th Commerce Solutions 14 Marketing and Marketing Mix

12th Commerce Guide Marketing and Marketing Mix Text Book Back Questions and Answers

I. Choose The Correct Answer.

Question 1.
The initial stage of Marketing system is ……………
a) Monopoly system
b) Exchange to money
c) Barter system
d) Self producing
Answer:
c) Barter system

Question 2.
Who is supreme in the market?
a) Customer
b) Seller
c) Wholesaler
d) Retailer
Answer:
a) Customer

Question 3.
In the following variables which one is not the variable of the marketing mix?
a) Place the variable
b) Product variable
c) Program variable
d) Price variable
Answer:
c) Program variable

Question 4.
Marketing mix means a marketing program that is offered by a firm to its target ………………… to earn profits through the satisfaction of their wants.
a) Wholesaler
b) Retailer
c) Consumer
d) Seller
Answer:
c) Consumer

Question 5.
Which one is the example of an Intangible product?
a) Education
b) Mobiles
c) Garments
d) Vehicles
Answer:
a) Education

II. Very Short Answer Questions.

Question 1.
What is Marketing?
Answer:
Marketing is one of the business functions that all activities that take place in relation to markets for actualise potential exchanges for the purpose of satisfying human needs and wants.

Question 2.
Define marketing mix.
Answer:
“Marketing mix is a pack of four sets of variables namely product variable, price variable, promotion variable, and place variable”

Question 3.
What is meant by Grading?
Answer:
Grading means the classification of standardized products into certain well-defined classes.

Question 4.
Define product.
Answer:
“A product is anything that can be offered to a market for attention, acquisition, use to consumption that might satisfy a want or a need” – PHILIP KOTLER

III. Short Answer Questions.

Question 1.
What are the objectives of marketing?
Answer:
Baker and Anshen say, “The end of all the marketing activities is the satisfaction of human wants”. The following are the objectives of marketing:

1. Intelligent and capable application of modem marketing policies.
2. To develop the marketing field.
3. To develop guiding policies and their implementation for a good result.

Question 2.
What is need for market and explain the concept of marketing?
Answer:
Market is needed for the following:

• To the movement of goods from the manufacturer to the consumer.
• To increase the standard of living of the people.
• To increase the national income
• To increase employment opportunities.

Concept of marketing:
What I can sell?

• Make what you can sell, but do not try to sell what you can make Shall I first create products?
• No, first create a consumer, then create products.

Shall I love my products?
No, love your customers not the products.

Who is supreme in the market?
Customer is supreme or king.
Who will shape my decision?
Customers’ preferences shape your decisions.

Question 3.
What are the factors affecting the Price of the Product? COMMO
Answer:
Factors affecting Price of product/service:
(a) Internal Factors:

1. Marketing Objectives
2. Marketing Mix Strategy
3. Organizational considerations
4. Costs
5. Organization Objectives

(b) External Factors:

1. The market after demand
2. Competition
3. Customers
4. Suppliers
5. Legal factors
6. Regulatory factors..

Question 4.
What do you mean by marketing mix? Describe any two elements.
Answer:

• Marketing mix means a marketing programme that is offered by a firm to its target consumers to earn profits through the satisfaction of their wants.
• It is a mixture of four ingredients namely 4Ps.
  • Product
  • Price
  • Place
  • Promotion.
  • Product
• “Product” is the main element of marketing.
• Without a product, there can be no marketing.
• Price is the value of a product expressed in monetary terms.
• t is the amount charged for the product.

IV. Long Answer Questions.

Question 1.
Discuss the evolution of marketing.
Answer:
Barter system:
Before the invention of money, goods were exchanged for goods.

Production orientation:

•  Producers more cared about the mass production of goods for the purpose of profit.
•  They cared very little about the customers.

Sales orientation:

• The stage witnessed a major change in all the spheres of economic life.
• Sales become the dominant factor, neglect the consumer needs and satisfaction.

Marketing orientation:
Customer’s importance was realized, but only as a means of disposing of goods aggressive advertising is used to compete for the stiff competition.

Consumer orientation:
Under this stage only such products are brought forward to the market which are capable of satisfying the tastes, preferences and expectations of consumer satisfaction.

Management orientation:
It assumes a managerial role to co-ordinate the business activities with the objective of planning, promoting and services to the present and potential consumers.

Question 2.
Why marketing is important to society and individual firms? Explain.
Answer:
To the Society:

•  Marketing is a connecting link between the consumers and the producers
•  Helps in increasing the living standard of people.
•  Helps in increasing the nation’s income.
•  Helps to increase employment opportunities.
•  II creates a modern cultivator.
•  Reduction in the cost of marketing is a direct benefit to society.
•  It includes all activities in the creation of Form, place, time, and possession utilities.

To the individual firms:

• It generates revenue [profit] to the firm.
• It helps the development of business and creates employment opportunities for people.
• It provides information to the top management for taking an overall decision on production
• Marketing and innovation are two basic functions of all business, the world is dynamic.

Question 3.
Narrate the elements of the marketing mix.
Answer:

Marketing mix means a marketing programme that is offered by a firm for the satisfaction of human wants. There are four elements of the marketing mix:

1. Product: A Product is the main element of marketing. Without a product, there can be no marketing.
2. Price: Price is the value of a product expressed in monetary terms. It is the amount charged for the product.
3. Place (Physical Distribution): An excellent quality product, with a good price, will be waste, if it is not transferred from the production place to the consumption place.
4. Promotion: An excellent product with a competitive price cannot achieve a desired success and acceptance in the market, with special features are conveyed to the consumers.

12th Commerce Guide Marketing and Marketing Mix Additional Important Questions and Answers

I. Choose The Correct Answer.

Question 1.
…………………………………….. Creates place utility.
a) Transport
b) Warehouse
c) Bank
d) Insurance
Answer:
a) Transport

Question 2.
Warehouse creates …………………………… utility.
a) Form
b) Place
c) Time
d) Possession
Answer:
c) Time

Question 3.
Before the invention of money, goods were exchanged for goods known as …………..
a) Trade
b) Commerce
c) Business
d) Barter
Answer:
d) Barter

Question 4.
Pick the odd one out:
a) Grading
b) Branding
c) Packing
d) Warehousing
Answer:
d) Warehousing

Question 5.
Pick the odd one out:
a) Price
b) Promotion
c) Place
d) Power
Answer:
d) Power

Question 6.
Choose the correct statement
i. Transport creates place utility.
ii. Were house creates time utility.
iii. Storage creates from utility

a) (i) and (ii) correct
b) (ii) and (iii) correct
c) All are correct
d) (i) and (ii) correct (iii) incorrect
Answer:
d) (i) and (ii) correct (iii) incorrect

Question 7.
Which one is not the correct method?
a) Promotion – Advertisement
b) Branding – Name
c) Packaging – Wrapping
d) Grading – Value
Answer:
d) Grading – value

Question 8.
Which of the following elements is the related marketing mix?
a) Place
b) production
c) consumption
d) trade
Answer:
a) place

II. Match The Following

Question 1.
Match list-1 with list-2

Answer:
a) (i) 4, (ii) 3, (iii) 2, (iv) 1

Question 2.
Match list-1 with list-2

Answer:
a) (i) 2, (ii) 4, (iii) 3, (iv) 1

III. Assertion and Reason.

Question 1.
Assertion [A]: Movement of goods from the place of production to the place of consumption by means of transport
Reason [R]: It creates place utility,
a) (A) is false (R) is true
b)(A) is true (R) is true
c) (A) is false (R) is false
d) (A) is true (R) is false
Answer:
b) (A) is True (R) is True

Question 2.
Assertion [ A]: Product is the main element of marketing.
Reason [R]: There can be no market without a product.
a) Both (A) and (R) are correct
b) Both (A) and (R) are incorrect
c) (A) is correct
d) (R) is correct
Answer:
a) Both (A) and (B) is correct

IV. Very Short Answer Questions.

Question 1.
Define marketing.
Answer:
“Marketing is concerned with the people and the activities involved in the flow of goods and services from the producer to the consumer”. -AMERICAN MARKETING ASSOCIATION.

Question 2.
What are the functions of exchange? BAS
Answer:

•  Buying
•  Assembling
•  Selling

Question 3.
Give the traditional marketing mix. 4Ps
Answer:

• Price
• Product
• Place
• Promotion

Question 4.
Give the modern marketing mix. 4Ps
Answer:

• People
• Performance
• Programme
• Process

Question 5.
What are the functions of marketing? G.B. GILES.
Answer:

•  Market research
•  Planning
•  Product development
•  Promotion
•  Distribution
•  Service offer sales

Question 6.
What are the functions of marketing? CLARK AND CLARK.
Answer:

•  Functions of exchange
•  Functions of physical supply
•  Facilitating functions.

Question 7.
Define price.
Answer:
“Price is the amount of money charged for a product or service or the sum of the values that consumers exchange for the benefits of having or using the product or service”. – PHILIP KOTLER

Question 8.
Give any two internal factors affecting the price of product/service. COMMO
Answer:

•  Costs
• Organizational objectives
•  Marketing objectives
•  Marketing mix strategy
•  Organizational consideration

V. Long Answer Questions.

Question 1.
Explain the functions of physical supply.
Answer:
Transportation:

•  Transport means carrying goods and services from one place to another. [Goods- men.]
•  It creates place utility by moving goods from the places when they are available in plenty to places where they are needed.
•  Types of transport – land, water, and air.

Storage:

•  Generally, there is a time gap between production and consumption of goods.
•  It involves the holding and preservation of goods from the time of production to the time of consumption.

Warehousing:
It creates time utility by storing the goods throughout the year and releasing them as and when they are needed.

Question 2.
What are the facilitating functions of marketing?
Answer:

• Financing: Long term – medium term and short term financing.
• Risk bearing: Time – place – competition – human and political risks.
• Grading: It means the classification of the standardized product into certain well-defined classes.
• Branding: It means giving a name or symbol to a product to differentiate it from a competitive product
• Packing: It means wrapping and crating of goods before distribution.
• Pricing: Price must be determined only to offer to take all the relevant factors into consideration.

Question 3.
What is marketing?
Answer:

• Marketing is one of the business functions that all activities that take place in relation to markets for actualizing potential exchanges [from the producer to the consumer] for the purpose of satisfying human needs and wants.
• Selling is basically concerned with putting the goods into the hands of the buyers for a price.
• But marketing is much wider than selling.
• It is an evolution rather than revolutionary.
• Marketing is what a marketer does. It is not clear to understand the meaning.
• It is one of the oldest professions in the world.
• The traditional objective of marketing had been to make the goods available at places where they are needed.
• This idea was later on changed by shifting the emphasis from exchange to satisfaction of human wants.
• Marketing must first find out what customers want and then plan a product to satisfy the wants.

Question 4.
State to advantages of warehousing.
Answer:
Storage:

• There is a time gap between production [supply] and consumption [demand].
• During the time gap, the goods may be damaged or destroyed or perished.
• For that goods need storage or warehouse.
• It creates time utility.

Equalization of demand and supply:

• It equalizes the demand and supply of goods.
• Storing the goods- when there is no demand.
• Releasing the goods – when there is a demand.

Price stabilization:

• It ensures price stabilization.
• It controls the price fluctuations.
• The price of commodities more or less uniform throughout the year by storing the goods, if there is no demand and releasing the goods if they are demanded.

Risk bearing:
When the goods are in the warehouse, in case of damage due to flood fire, theft, etc., the warehouse keepers compensate the loss of the owner of the goods.

Finance:
By pledging warehouse receipt or warehouse warrant, a depositor can get loans from financial institutions.

Question 5.
How market information is helpful to the invention of a new product in the market?
Answer:

•  Strong knowledge of customers.
•  Marketing research – process for marketing opportunities- problem-solving collecting- analyzing marketing information.
• Control over fact – the responsibility of the marketing research director.
• Design research carefully and supervise its execution.
• Various combinations of people, technologies for managing marketing information.
• Broader management and strategy decisions.
• Research consumer performance to contribute to improving decision-making performance.
• It is helpful to accurate needs and decision-making by the marketer to be a regular source of information about marketing and trading brand awareness.

Tamilnadu State Board New Syllabus Samacheer Kalvi 12th Commerce Guide Pdf Chapter 13 Concept of Market and Marketer Text Book Back Questions and Answers, Notes.

Tamilnadu Samacheer Kalvi 12th Commerce Solutions Chapter 13 Concept of Market and Marketer

12th Commerce Guide Concept of Market and Marketer Text Book Back Questions and Answer

I. Choose The Correct Answer.

Question 1.
One who promotes (or) Exchange of goods or services for money is called as ……………
a) Seller
b) Marketer
c) Customer
d) Manager
Answer:
b) Marketer

Question 2.
The marketer initially wants to know in the marketing is …………………….
a) Qualification of the customer
b) Quality of the product
c) Background of the customers
d) Needs of the customers
Answer:
d) Needs of the customers

Question 3.
The Spot market is classified on the basis of ………………..
a) Commodity
b) Transaction
c) Regulation
d) Time
Answer:
b) Transaction

Question 4.
Which one of the market deals in the purchase and sale of shares and debentures?
a) Stock Exchange Market
b) Manufactured Goods Market
c) Local Market
d) Family Market
Answer:
a) Stock Exchange Market

Question 5.
Stock Exchange Market is also called …………
a) Spot Market
b) Local Market
c) Security Market
d) National Market
Answer:
c) Security Market

II. Very Short Answer Questions.

Question 1.
What is the Market?
Answer:
The word market is derived from the Latin word ‘Marcatus’ which means trade, commerce, merchandise, a place where the business is transacted.

Question 2.
Define Marketer.
Answer:
“A person whose duties include the identification of the goods and services desired by a set of consumers, as well as the marketing of those goods and services on behalf of a company” – BUSINESS DICTIONARY

Question 3.
What is meant by Regulated Market?
Answer:
Very Short Period Market: Markets that deal in perishable goods like, fruits, milk, vegetables, etc., are called a very short period market.

Question 4.
What is meant by Spot Market?
Answer:
In such markets, goods are exchanged and the physical delivery of goods takes place immediately.

Question 5.
What is meant by Commodity Market?
Answer:
A commodity market is a place where produced goods or consumer goods are bought and sold.

III. Short Answer Questions.

Question 1.
What can be marketed in the Market? [S.GOPI PEEPI]
Answer:

• Services
• Goods
• Organization
• Persons
• Ideas
• Places
• Events
• Experiences
• Properties
• Information

Question 2.
Mention any three Roles of the Marketer.
Answer:
Instigator:
As an Instigator, He keenly watches the developments taking place in the market and identifies marketing opportunities emerging in the ever-changing market.

Innovator:

• Marketer seeks to distinguish his product or services by adding additional features or functionalities to the existing products.
• Modifying the pricing structure, introducing new delivery patterns, creating new business models, introducing changes in the production process, and so on.
• Implementer: Marketer plays the role of implementer when he or she actually converts marketing opportunities into marketable products with the help of several functional teams put in place in the organization.

Question 3.
The marketer is an innovator? Do you agree?
Answer:
Marketer seeks to distinguish his products/services by adding additional features or functionalities to the existing product, modifying the pricing structure, introducing new delivery patterns, creating new business models, introducing change in production process and so on.

Question 4.
Explain the types of markets on the basis of time.
Answer:
Very Short Period Market:
Markets which deal in perishable goods like milk, Fish, Fruits, Vegetables, etc. are called as “Very Short Period Market”.

Short Period Market:
In certain goods, supply is adjusted to meet the demand. The demand is greater than supply. (Rice, wheat, etc) such markets are known as “Short Period Marker.

Long Period Market:
This type of market deals in durable goods. [TV – Fridge – computer etc] where the goods and services are dealt for longer period usages.

Question 5.
List down the functions of Marketer? [GM] [5-P] [BTSS]
Answer:

1. Very Short Period Market: Markets which deal in perishable goods like, fruits, milk, vegetables, etc., are called a very short period market. There is no change in the supply of goods.
2. Short Period Market: In certain goods, supply is adjusted to meet the demand. The demand is greater than supply. Such markets are known as Short Period Market.
3. Long Period Market: This type of market deals in durable goods, where the goods and services are dealt with for a longer period of usages.

IV.Long Answer Questions.

Question 1.
How the Market can be classified? GTTV RICE
Answer:

Question 2.
How the market can be classified on the basis of Economics?
Answer:
The Market can be classified on the basis of Economics as follows:
(a) Perfect Market: A market is said to be a perfect market if it satisfies the following conditions:

1. A large number of buyers and sellers are there.
2. Prices should be uniform throughout the market.
3. Buyers and sellers have a perfect knowledge of the market.
4. Goods can be moved from one place to another without restrictions.

(b) Imperfect Market: A market is said to be imperfect when

1. Products are similar but not identical.
2. Prices are not uniform.
3. There is a lack of communication.

12th Commerce Guide Concept of Market and Marketer Additional Important Questions and Answers

I. Choose The Correct Answer.

Question 1.
One who promotes (or) Exchange of goods or services for money is called as _____
(a) Seller
(b) Marketer
(c) Customer
(d) Manager
Answer:
(b) Marketer

Question 2.
Mercatus Mean ……….
a) A place where the business is transacted
b) A place where goods are produced
c) A place where manufacturers assembled
d) All of these
Answer:
a) A place where the business is transacted

Question 3.
The Need for the market is ……………………..
a) To Exchange
b) To adjust the price mechanism
c) To improve the quality
d) All the above
Answer:
d) All the above

Question 4.
Which one of the market deals in the purchase and sale of shares and debentures?
(a) Stock Exchange Market
(b) Manufactured Goods Market
(c) Local Market
(d) Family Market
Answer:
(a) Stock Exchange Market

Question 5.
In …………………. market physical delivery of goods takes place immediately.
a) Future market
b) Spot market
c) Capital market
d) Commodity market
Answer:
b) Spot market

Question 6.
Short term securities are exchanged in ……………… market.
a) Stock
b) Finance
c) Money
d) All of the above
Answer:
c) Money

Question 7.
Stock Exchange Market is also called _____
(a) Spot Market
(b) Local Market
(c) Security Market
(d) National Market
Answer:
(d) National Market

Question 8.
Which one is not correctly matched?
a) Very short period market – Vegetables
b) Future market – Delivery
c) Regulated market – No statutory measures
d) Bullion market – Gold
Answer:
c) Regulated market – No statutory measures

Question 9.
Which of the following statement correct?
i) In imperfect market products are similar but not identical.
ii) Prices are not uniform.
iii) There is a lack of communication.

a) (i) is correct
b) (ii) and (iii) are correct
c) (i) and (ii) are correct
d) All (i), (ii) and (iii) are correct
Answer:
d) All (i), (ii) and (ii) are correct

II. Match The Following.

Question 1.
Match List-I with List-II

a) (i) – 2 (ii) – 1 (iii) – 4 (iv) – 3
b) (i) – 4 (ii) – 3 (iii) – 2 (iv) – 1
c) (i) – 3 (ii) – 2 (iii) – 1 (iv) – 4
d) (i) – 1 (ii) – 4 (iii) – 3 (iv) – 2
Answer:
a) (i) – 2 (ii) – 1 (iii) – 4 (iv) – 3

Question 2.
Match List-I with List-II

a) (i) – 4 (ii) – 3 (iii) – 2 (iv) – 1
b) (i) – 3 (ii) – 2 (iii) – 1 (iv) – 4
c) (i) – 2 (ii) – 3 (iii) – 4 (iv) – 1
d) (i) – 1 (ii) – 4 (iii) – 3 (iv) – 2
Answer:
a) (i) – 4 (ii) – 3 (iii) – 2 (iv) – 4

III. Assertion and Reason.

Question 1.
Assertion (A): A market is said to be a perfect market.
Reason (R): There is a Large number of buyers and sellers.
a) (A) is True (R) is False
b) (A) is False (R) is True
c) Both (A) and (R) are True
d) Both (A) and (R) are False
Answer:
c) Both (A) and (R) are True

IV. Short Answer Questions.

Question 1.
Mention any three Roles of the Marketer.
Answer:

1. Instigator: As an instigator, the marketer keenly watches the developments taking place in the market and identifies marketing opportunities emerging in the ever-changing market.
2. Integrator: The marketer plays the role of the integrator in the sense that he collects feedback or vital inputs from channel members and consumers.
3. Implementer: Marketer plays the role of implementer when he/she actually converts marketing opportunities into marketable products.

Question 2.
Classify the market on the basis of Importance.
Answer:
Primary market:
The primary producers of firms sell their output or products through this type of market to wholesales or consumers.

Secondary market:

• In this market, semi-finished goods are marketed.
• The dealings commonly between wholesales and retailers.

Terminal market:
It is a central place that serves as an assembly and trading place for commodities in a
metropolitan area.

Question 3.
List down the functions of Marketer.
Answer:

1. Gathering and Analysing market information
2. Market planning
3. Product Designing and development
4. Standardization and Grading
5. Packaging and Labelling
6. Branding
7. Customer Support Services
8. Pricing of Products
9. Promotion and Selling
10. Physical Distribution
11. Transportation
12. Storage and Warehousing

Question 4.
Define Market.
Answer:
“Market includes both place and region in which buyers and sellers are in free competition with one another” – PYLE.

Question 5.
Explain the Need for marketing.
Answer:

•  To Exchange [Barter] Goods and Services
•  To Adjust Demand and Supply by the price mechanism.
•  To improve the quality of life of the Society.

Question 6.
Mention any four differences between Wholesale Market and Retail Market? [LOQS]
Answer:

Question 7.
Why Customer support is needed to Market?
Answer:

•  To exchange (Barter) goods and services.
•  To adjust demand and supply by the price mechanism.
•  To improve the quality of life of the society, [standard of living]
•  To introduce new modes of life.
•  To develop by enhancing the market segment.

V. Long Answer Questions.

Question 1.
How the market can be classified?
Answer:
On the basis of different approaches markets can be classified as follows:
I. On the basis of Geographical Area:

• Family Market
• Local Market
• National Market
• International Market or World Market

II. On the Basis of Commodities / Goods:
(a) Commodity Market

• Produce Exchange Market
• Manufactured Goods Market
• Bullion Market

(b) Capital Market:

• Money Market
• Foreign Exchange Market
• The Stock Market

III. On the Basis of Economics:

• Perfect Market
• Imperfect Market

IV. On the basis of transaction:

• Spot Market
• Future market

V. On the Basis of Regulation:

• Regulated Market
• Unregulated Market

VI. On the Basis of Time:

• Very Short Period Market
• Short Period Market
• Long Period Market

VII. On the Basis of Volume of Business:

• Wholesale Market
• Retail Market

VIII. On the Basis of Importance:

• Primary Market
• Secondary Market
• Terminal Market

Question 2.
How the market can be classified on the basis of commodities [Goods]?
Answer:
A) Commodity Market:
A commodity market is a place where produced goods or consumer goods are bought and sold.

1. Produce Exchange Market: It is an organised market where commodities or Agricultural produce are Bought and sold on a wholesale basis.
2. Manufactured Goods Market: This market deals with [Leather goods, machinery, etc] manufactured goods.
3. Bullion Market: This market deals with the purchase and sale of Gold and Silver.

B) Capital Markets:

1. Money Market: It is a type of market where short term securities are exchanged. [Banks, – Finance to industries] .
2. Foreign Exchange Market: This type of market, help Exporters and Importers, in converting their currencies into Foreign currencies and vice versa.
3. Stock Market: This is a market where the purchase and sales of shares and Debentures, Bonds, etc. of companies are dealt with.

Question 3.
What is your contribution to promote the market in modern society?
Answer:
A market is a place where buyers and sellers gather for purchase and sale. The market may be of Local market, national market, and international or global market. To develop and promote the market the following are needed:

1. Eligible and satisfied and customer is needed.
2. Quality and durable goods are to be marketed.
3. Recent trends like E-marketing, online marketing are to be encouraged.
4. After-sales service is to be provided to durable goods.
5. Customers are to be financed for buying costly articles.
6. New Innovations and marketing research are to be introduced to develop the market.

Question 4.
Apart from goods and services, explain any five items that can be marketed,
Answer:
i) Experiences:
The unique and varied experiences pertaining to a place or a park or an event can be marketed under this concept. For eg. Amusement Park, Theme Park, Mountaineering, etc.

ii) Events:
The event marketing aims at promoting and marketing special events, shows, exhibitions, fairs, performances, sports events like the World Cup, Olympics, T20, etc.

iii) Properties:
Properties include both real property and financial property which involve the transfer of ownership on sale or purchase of the same. For eg. Constructed house, Land, Plot, Building.

iv) Organisations:
An organisation can market itself in order to build an image for it by sponsoring events, adoption of villages, donations for charitable causes, corporate social responsibility activities, etc.

v) Ideas:
An idea may change the world. Innovative and attractive ideas are desirable products for marketers to sell. Social media marketing thrives on new ideas in a consistent manner.

Tamilnadu State Board New Syllabus Samacheer Kalvi 12th Chemistry Guide Pdf Chapter 10 Surface Chemistry Text Book Back Questions and Answers, Notes.

Tamilnadu Samacheer Kalvi 12th Chemistry Solutions Chapter 10 Surface Chemistry

12th Chemistry Guide Surface Chemistry Text Book Questions and Answers

Part – I Text Book Evaluation

I. Choose the correct answer

Question 1.
For freudlich isotherm a graph of log \(\frac{x}{m}\) is plotted against log P. The slope of the line and its y – axis intercept respectively corresponds to
(a) \(1 / n\), k
(b) log \(1 / n\), k
(c) \(1 / n\), log k
(d) log \(1 / n\), log k
Answer:
(c) \(1 / n\), log k
\(\frac{x}{m}\) = \(\mathrm{k} \cdot \mathrm{p}^{1 / \mathrm{n}}\)
log\((\frac{x}{m})\) = log k + \(\frac { 1 }{ n }\)log p
y = c + mx
m = \(\frac { 1 }{ n }\) and c = log k

Question 2.
Which of the following is incorrect for physisorption?
(a) reversible
(b) increases with increase in temperature
(c) low heat of adsorption
(d) increases with increase in surface area
Answer:
(b) increases with increase in temperature

Question 3.
Which one of the following characteristics are associated with adsorption?
(a) ∆G and ∆H are negative but ∆S is positive
(b) ∆G and ∆S are negative but ∆H is positive
(c) ∆G is negative but ∆H and ∆S are positive
(d) ∆G. AH and ∆S all are negative.
Answer:
(d) ∆G, ∆H and ∆S all are negative.
Adsorption leads to decrease in randomness (entropy).i.e. ∆S < 0 for the adsorption to occur, ∆G should be – ve. We know that ∆G = ∆H – T∆S if ∆S is – ve, T∆S is + ve. It means that ∆G will become negative only when ∆H is – ve and ∆H > T∆S

Question 4.
Fog is colloidal solution of ……………..
(a) solid in gas
(b) gas in gas
(c) liquid in gas
(d) gas in liquid
Answer:
(c) liquid in gas
dispersion medium-gas, dispersed phase-liquid

Question 5.
Assertion: Coagulation power of Al³⁺ is more than Na.
Reason: greater the valency of the flocculating ion added, greater is its power to cause precipitation
(a) if both assertion and reason are true and reason is the correct explanation of assertion.
(b) if both assertion and reason are true but reason is not the correct explanation of assertion.
(c) assertion is true but reason is false
(d) both assertion and reason are false
Answer:
(a) if both assertion and reason are true and reason is the correct explanation of assertion. (Hardy-Sechuize nile)

Question 6.
Statement: To stop bleeding from an injury, ferric chloride can be applied. Which comment about the statement is justified?
(a) It is not true, ferric chloride is a poison.
(b) It is true, Fe³⁺ ions coagulate blood which is a negatively charged sol
(c) It is not true; ferric chloride is ionic and gets into the blood stream.
(d) It is true, coagulation takes place because of formation of negatively charged sol with Cl^–.
Answer:
(b) It is true, Fe³⁺ ions coagulate blood which is a negatively charged sol

Question 7.
Hair cream is …………..
(a) gel
(b) emulsion
(c) solid sol
(d) sol.
Answer:
(b) emulsion
Emulsion dispersed phase, Dispersion medium -liquid

Question 8.
Which one of the following is correctly matched?
(a) Emulsion – Smoke
(b) Gel – butter
(c) foam – Mist
(d) whipped cream – sol
Answer:
(b) Gel – butter

Question 9.
The most effective electrolyte for the coagulation of As₂S₃ Soils
(a) NaCl
(b) Ba(NO₃)₂
(c) K₃[Fe(CN)₆]
(d) AI₂(SO₄)₃
Answer:
(d) AI₂(SO₄)₃

Question 10.
Which one of the is  not a surfactant?
(a) CH₃ – (CH₂)₁₅ – N – (CH₃)₂CH₂Br
(b) CH₃ – (CH₂)₁₅ – NH₂
(c) CH₃ – (CH₂)₁₆ – CH₂OSO₂ – Na⁺
(d) OHC – (CH₂)₁₄ – CH₂ – COO^–Na⁺
Answer:
(b) CH₃ – (CH₂)₁₅ – NH₂

Question 11.
The phenomenon observed when a beam of light is passed through a colloidal solution is ………….
(a) Cataphoresis
(b) Electrophoresis
(c) Coagulation
(d) Tyndall effect
Answer:
(d) Tyndall effect-scattering of light

Question 12.
In an electrical field, the particles of a colloidal system move towards cathode. The coagulation of the same sol is studied using K₂SO₄
(i). Na₃PO₄
(ii). K₄[Fe(CN)₆]
(iii). and NaCI
(iv). Their coagulating power should be …………..
(a) II > I >IV > III
(b) III > II > I > IV
(c) I > II > III > IV
(d) none of these
Answer:
(b) III > II > I > IV

Question 13.
Collodion is a 4% solution of which one of the following compounds in alcohol – ether mixture?
(a) Nitroglycerine
(b) Cellulose acetate
(c) Glycoldinitrate
(d) Nitrocellulose
Answer:
(a) Nitrocellulose
pyroxylin (nitro cellulose)

Question 14.
Which one of the following is an example for homogeneous catalysis?
(a) manufacture of ammonia by Haber’s process
(b) manufacture of sulphuric acid by contact process
(c) hydrogenation of oil
(a) Hydrolysis of sucrose in presence of all HCI
Answer:
(a) Hydrolysis of sucrose in presence of all HCl
Both reactant and catalyst are in same phase. i.e. (1)

Question 15.
Match the following.

Answer:
(a) (iv) (i) (ii) (iii)

Question 16.
The coagulation values in millimoles per litre of the electrolytes used for the coagulation of AS₂S₃ are given below
(I) (NaCl) = 52
(II) (BaCl) = 0.69
(III) (MgSO₄) = 0.22
The correct order of their coagulating power is ……….
(a) III > II > I
(b) I > II > III
(c) I >III > II
(d) II > III > I
Answer:
(a) III > II > I

Question 17.
Adsorption of a gas on solid metal surface is spontaneous and exothermic, then ……………
(a) ∆H increases
(b) ∆S increases
(c) ∆G increases
(d) ∆S decreases
Answer:
(a) ∆S decreases – ∆S is -ve

Question 18.
If x is the amount of adsorbate and m is the amount of adsorbent, which of the following relations is not related to adsorption process?
(a) x/m = f(P) at constant T
(b) x/m = f(T) at constant P
(c) P = f(T) at constant x/m
(d) x/m = PT
Answer:
(d) x/m = mPT

Question 19.
On which of the following properties does the coagulating power of an ion depend?
(a) Both magnitude and sign of the charge on the ion.
(b) Size of the ion alone
(c) the magnitude of the charge on the ion alone
(d) the sign of charge on the ion alone.
Answer:
(a) Both magnitude and sign of the charge on the ion.

Question 20.
Match the following.

II. Short Answer Questions

Question 1.
Give two important characteristics of physisorption.
Answer:
Important characteristics of physisorption:

1. It is reversible
2. It has low heat of adsorption
3. It has weak van der Waals forces of attraction with the adsorbent.
4. It increases with an increase in pressure.
5. It forms multi molecular layer.

Question 2.
Differentiate physisorption and chemisorption.
Answer:
Chemical adsorption or Chemisorption or Activated adsorption

1. It is very slow
2. It is very specific depends on nature of adsorbent and adsorbate.
3. chemical adsorption is fast with increase pressure, it can not alter the amount.
4. When temperature is raised chemisorption first increases and then decreases.
5. Chemisorption involves transfer of electrons between the adsorbent and adsorbate, Heat of adsorption is high i.e., from 40 – 400kJ/mole.
6. Monolayer of the adsorbate is formed.
7. Adsorption occurs at fixed sites called active centres. It depends on surface area.
8. Chemisorption involves the formation of activated complex with appreciable activation energy.
9. Physical adsorption or van der Waals adsorption or Physisorptlon
10. It is irreversible.

Physical adsorption or van der Waals adsorption or physisorption.

1. It is instantaneous
2. It is non-specific
3. In Physisorption. when pressure increases the amount of adsorption increases.
4. Physisorption decreases with increase in temperature.
5. No transfer of electrons
6. Heat of adsorption is low in the order of 40kJ/mole.
7. Multilayer of the adsorbate is formed on the adsorbent.
8. It occurs on all sides.
9. Activation energy is insignificant.
10. It is reversible.

Question 3.
In case of chemisorption, why adsorption first increases and then decrease with temperature?
Answer:
1. Chemisorption involves high activation energy so it is also referred to as activated adsorption.

2. It is found in chemisorption that it first increases and then decreases with an increase in temperature. When adsorption is plotted, the graph first increases and then decreases with temperature.

3. The initial increase illustrates the requirement of activation of the surface for adsorption is due to fact that the formation of activated complex requires certain energy. But later it decreases at high temperature is due to desorption as the kinetic energy of the adsorbate increases (exothermic nature)

Question 4.
Which will be adsorbed more readily on the surface of charcoal and why; NH₃ or CO₂?
Answer:
1. The gases having low critical temperature are adsorbed slowly, while gases with high critical temperature are adborbed readily.

2. Among CO₂, and NH₃, NH₃ will be more readily adsorbed on the surface of the charcoal. This is because the critical temperature of ammonia gas is quite high than the CO₂. Hence, it easily combines with the materials than the CO₂ whether it is solid, liquid or any gases.

Question 5.
Heat of adsorption is greater for chemisorptions than physisorption. Why?
Answer:
Chemisorption has higher heat of adsorption. because in chemisorption the chemical bonds are much stronger. In adsorbed state the adsorbate is hold on the surface of adsorbent by attractive forces (bond). And chemisorption is irreversible one. Therefore, heat of adsorption is greater for chenil sorptions than physisorption. Chemisorption, heat of adsorption range 40 – 400kJ/mole.

Question 6.
In a coagulation experiment 10 mL of a colloid (X) is mixed with distilled water and 0.1M solution of an electrolyte AB so that the volume is 20 mL. It was found that all solutions containing more than 6.6 mL of AB coagulate with in 5 minutes. What is the flocculation values of AB for sol (X)?
Answer:
A minimum of 6.6mL of AB is required to coagulate the sol. The moles of AB in the sol is
\(\frac{6.6 \times 0.01}{20}\) = 0.033 moles
This means that a minimum of 0.033 moles or 0.0033 x 1000 = 3.3 milli moles are required for coagulating one litre of sol. Flocculation value of AB for X = 3.3

Question 7.
Peptising agent is added to convert precipitate into colloidal solution. Explain with an example.
Answer:
1. Ions either positive or negative of peptizing agent (electrolyte) are adsorbed on the particles of precipitate. They repel and hit each other and break the particles of the precipitate into colloidal size.

2. For example, when we add a small volume of very dilute hydrochloric acid solution peptising agent to a fresh precipitate of a silver chloride, it leads to formation of silver chloride colloidal solution,

Question 8.
What happens when a colloidal sol of Fe(OH)₃ and As₂S₃ are mixed?
Answer:
On mixing Fe(OH)₃ positive sol and As₂S₃ negative sol, mutual coagulation occurs which causes precipitation. When this sol got mixed with each other, due to Fe³⁺ and S^2- ions neutralisation of charges will happen, and precipitate will be formed.
Fe(OH)₃ + As₂S₃ → Fe₂S₃ + As(OH)₃

Question 9.
What is the difference between sol and gel?
Answer:
Sol

1. The liquid state of a colloidal solution is called a sol.
2. The sol does not have a definite structure.
3. The dispersion medium of the sol may be water.
4. The sol can be converted to gel by cooling The sol can be easily dehydrated.
5. The viscosity of the sol is very low.
6. Sol is categorized into lyophobic and lyophilic sols.
7. Example: Blood

Gel

1. The solid or semi-solid state of a colloidal solution is called gel.
2. The gel possesses a honeycomb-like structure.
3. The dispersion medium of gel will be hydrated colloid particles.
4. The gel can be converted to sol by heating.
5. The gel cannot be dehydrated.
6. The viscosity of the gel is very high.
7. There is no such classification of gel.
8. Example: Fruit jelly, cooked gelatin jelly.

Question 10.
Why are lyophillic colloidal sols are more stable than lyophoblic colloidal sol?
Answer:
1. A lyophilic colloidal sols are stable due to the charge and the hydration of sol particles.

2. Lyophilic sols are more stable than lyophobilc sols because they are highly hydrated in the solution. And since more is the hydration more will be its stability.

3. Lyophilic sols are stabilized by electrostatic charge and hydration whereas lyophobic sols are only stabilized by charge, so they easily gets coagulated and requires a stabilising agent. Hence, lyophilic sols are more stable than lyophobilc sols.

Question 11.
Addition of Alum purifies water. Why?
Answer:
Purification of drinking water is activated by coagulation of suspended impurities in water using alums containing Al³⁺. That is why we are adding to purify water.

Question 12.
What are the factors which influence the adsorption of a gas on a solid?
Answer:
Factors that influence the adsorption of a gas on a solid is as follows:
1. Nature of the gas:
Easily liquefiable gases such as NH₃, HCl etc are adsorbed to a great extent in comparison to gases such as H₂, O₂ etc. This is because van der Waal’s forces are stronger is easily liquifiable gases.

2. Surface area of the solid:
The greater the surface area of the adsorbent, the greater is the adsorption of gas on the solid surface.

3. Effect of pressure:
Adsorption is a reversible process and is accompanied by a decrease in pressure. Therefore, adsorption increases with an increase in pressure.

4. Effect of temperature:
Adsorption is an exothermic process. Thus in accordance with Le – Chatelier’s principle, the magnitude of adsorption decreases with an increase in temperature.

Question 13.
What are enzymes? Write a brief note on the mechanism of enzyme catalysis.
Answer:
Enzymes are complex protein molecules with three-dimensional structures. They catalyse the chemical reaction in a living organism. They are often present in colloidal state and extremely specific in catalytic action.

Each enzyme produced in a particular living cell can catalyse a particular reaction in the cell. Mechanism of enzyme catalysis: Mechanism of enzyme catalysed reaction is known as lock and key mechanism.
1. Enzymes arc highly specific in their action.

2. This specificity is due to the pressure of active sites. The shape of active site of any given enzyme is like cavity such that only a specific substrate can fit into it.

In the same way a key fits into lock. The specific binding needs to the formation of an enzyme-substrate complex which accounts for high specificity of enzyme catalysed reactions.

3. Once the proper orientation is attained the substrate molecules reacts to form the product in two steps.

4. Since product molecules do not have any affinity for the enzyme they leave the enzyme surface making room for fresh substrate.

step 1: Formation of the enzyme-substrate complex

Step 2: Dissociation of the enzyme-substrate complex to form product

The rate of the formation of the product depends upon the concentration of ES.

Question 14.
What do you mean by activity and selectivity of catalyst?
Answer:
1. Activity of Catalyst:
The activity of a catalyst is its ability to increase the rate of a particular reaction, Chemisorption is the main factor in deciding the activity of a catalyst. The adsorption of reactants in the catalyst surface should be neither too strong nor too weak. It should just be strong enough to make the catalyst active.

2. Selectivity of the catalyst:
The ability of the catalyst to direct a reaction to yield a particular product is referred to as the selectivity of the catalyst. For example, by using different catalysts, we can get different products for the reaction between H₂ and CO.

Question 15.
Describe some features of catalysis b Zeoliles.
Answer:
1. Zeolites are microporous, crystalline, hydrated aluminosilicates, made of silicon and aluminium tetrahedra.

2. There are about 50 natural zeolites and 1 50 synthetic zeolites. As silicon is tetravalent and aluminium is trivalent, the zeolite matrix carries extra negative charge. To balance the negative charge, there are extra framework cations for example, H⁺ or Na⁺ ions.

3. Zeolites earring protons are used as solid acids, catalysis and they are extensively used in the petrochemical industry for cracking heavy hydrocarbon fractions into gasoline, diesel,etc.

4. Zeolites earring Na ions are used as basic catalysis.

5. One of the most important applications of zeolites is their shape selectivity. In zeolites, the active sites namely protons are lying inside their pores. So, reactions occur only inside the pores of zeolites.

Question 16.
Give three uses of emulsions.
Answer:

1. The cleansing action of soap is due to emulsions.
2. It is used in the preparation of vanishing cream.
3. It is used in the preparation of cold liver oil.

Question 17.
Why does the bleeding stop by rubbing moist alum?
Answer:
Blood is a colloidal sol. When we nib the injured part with moist alum then coagulation of blood takes place. Hence main reason is coagulation, which stops the bleeding. Therefore bleeding stop by rubbing moist alum.

Question 18.
Why is desorption important for a substance to act as good catalyst?
Answer:
Desorption is important for a substance to act as a good catalyst, so that after the reaction, the products found on the surface separate out (desorbed) to create free surface again for other reactant molecules to approach the surface and react. If desorption does not occur then other reactants are left with no space on the surface of the catalyst for adsorption and the reaction will stop.

Question 19.
Comment on the statement: Colloid is not a substance but it is a state of the substance.
Answer:
The statement is true. Because the same substance may exist as a colloid under certain conditions and as a crystalloid under certain other conditions. For example. NaCl in water behaves as a crystalloid while in benzene, it behaves as a colloid. Similarly, dilute soap solution behaves

like a crystalloid while concentrated solutions behave as a colloid. It is the size of the particles which matters. That is the state in which the substance exists. If the size of the particles lies in the range 1 nm to 1oo nm, it is in the colloidal state.

Question 20.
Explain any one method for coagulation
Answer:
The flocculation and setting down of the soil particles is called coagulation. Various method of coagulation are given below:

1. Addition of electrolytes
2. Electrophoresis
3. Mining oppositely charged sols
4. Boiling.

Addition of electrolytes
A negative ion causes the precipitation of positively charged sol and vice versa. When the valency of ion is high, the precipitation power is increased. For example, the precipitation power of some cations and anions varies in the following order
Al³⁺ > Ba²⁺ > Na⁺, Similarly [Fe(CN)₆]^-3 > SO₄^-2 > Cl^–
The precipitation power of electrolyte is determined by finding the minimum concentration (millimoles / lit) required to cause precipitation of a sol in 2hours. This value is called flocculation value. The smaller the flocculation value greater will be precipitation.

Question 21.
Write a note on electroosmosis.
Answer:
Electro osmosis:
A sol is electrically neutral. Hence the medium carries an equal but opposite charge to that of dispersed particles. When sol particles are prevented from moving, under the influence of electric field the medium moves in a direction opposite to that of the sol particles. This movement of dispersion medium under the influence of electric potential is called electro-osmosis.

Question 22.
Write a note on catalytic poison
Answer:
Catalytic poison:
Certain substances when added to a catalysed reaction, decreases or completely destroys the activity of catalyst and they are often known as catalytic poisons. For example, In the reaction,
2SO₂ + O₂ → 2SO₃ with a Pt catalyst, the poison is AS₂O₃.
i.e., AS₂O₃ destroys the activity of pt. AS₂O₃ blocks the activity of the catalyst. So, the activity is lost.

Question 23.
Explain intermediate compound formation theory of catalysis with an example.
Answer:
The intermediate compound formation theory:
A catalyst acts by providing a new path with low energy of activation. in homogeneous catalysed reactions a catalyst may combine with one or more reactant to form an intermediate which reacts with other reactant or decompose to give products and the catalyst is regenerated.

Consider the reactions:
A + B → AB ……………(1)
A + C → AC (intermediate) ………….(2)
C is the catalyst
AC + B → AB + C …………(3)
Activation energies for the reactions (2) and (3) are lowered compared to that of (1). Hence the formation and decomposition of the intermediate accelerate the rate of the reaction.
Example:
The mechanIsm of Fridel crafts reaction is given below

The action of catalyst is explained as follows .

This theory describes,

1. The specificity of a catalyst.
2. The increase in the rate of the reaction with increase in the concentration of a catalyst.

Limitations

1. The intermediate compound theory fails to explain the action of catalytic poison and activators (promoters).
2. This theory is unable to explain the mechanism of heterogeneous catalysed reactions.

Question 24.
What is the difference between homogenous and hetrogenous catalysis?
Answer:
Hornogenous Catalysis:

1. In a catalysed reaction the reactants, products and catalyst are present in the same phase.
2. For example.
   
   Hence NO act as catalyst.
3. Homogeneous catalysis explained by intermediate compound formation theory.

Heterogeneous Catalysis:

1. In a reaction, the catalyst is present in a different phase. i.e., catalyst is not present in the same phase as that of reactants and products.
2. For example.
   
   Hence Pt(s) act as catalyst.
3. Hetenogeneous catalysis explained by adsorption theory.

Question 25.
Describe adsorption theory of catalysis.
Answer:
Langmuir explained the action of catalyst in heterogeneous catalysed reactions based on adsorption.
This theory explains heterogeneous catalysis.
The reactant molecules are adsorbed on the catalytic surface, so heterogeneous catalysis is also called as contact catalysis.
When the reactants are adsorbed on the catalytic surface, an activated complex is formed.
This activated complex decomposes to give the product.
Steps involved in heterogeneous catalysis.

1. Reactant molecules diffuse from bulk to the catalyst surface.
2. Reactant molecules are adsorbed on the surface of the catalyst.
3. Adsorbed reactant molecules are activated to form activated complex which is decomposed to form the products.
4. Product molecules are desorbed.
5. Product molecules diffuse away from the surface of the catalyst.

12th Chemistry Guide Surface Chemistry Additional Questions and Answers

Part – II – Additional Questions

I. Choose the correct answer

Question 1.
Adsorption is a
a) Bulk phenomenon
b) Surface phenomenon
c) Both (a) and (b)
d) None of the above
Answer:
b) Surface phenomenon

Question 2.
Absorption is a
a) Bulk phenomenon
b) Surface phenomenon
c) Both (a) and (b)
d) None of the above
Answer:
a) Bulk phenomenon

Question 3.
Which among the following is an adsorbent?
a) N₂
b) SO₂
c) Ni
d) NH₃
Answer:
c) Ni

Question 4.
In adsorption, if the concentration of a substance in the interface is high, then it is called?
a) Desorption
b) Positive adsorption
c) Negative adsorption
d) Absorption
Answer:
b) Positive adsorption

Question 5.
Adsorption process is
a) Spontaneous
b) Non-spontaneous
c) Slow
d) Bulk phenomenon
Answer:
a) Spontaneous

Question 6.
Adsorption is always accompanied by
a) Increase in entropy
b) Increase in free energy
c) Decrease in free energy
d) No change in entropy
Answer:
c) Decrease in free energy

Question 7.
The force of attraction exist between adsorbent and adsorbate in physical adsorption is
a) Vanderwaal’s force
b) Dipole-dipole interaction
c) Dispersion forces
d) All the above
Answer:
d) All the above

Question 8.
Total amount of the gas adsorbed increases as the ……………. of the adsorbent increases.
a) Volume
b) Density
c) Surface area
d) Surface tension
Answer:
c) Surface area

Question 9.
The critical temperature of the gas which is readily adsorbed is
a) lower
b) higher
c) zero
d) none of the above
Answer:
b) higher

Question 10.
Which among the following gas is adsorbed slowly?
a) SO₂
b) NH₃
c) N₂
d) CO₂
Answer:
c) N₂
Reason: Critical temperature of N₂ is low hence adsorbed slowly.

Question 11.
The process of adsorption is
a) Exothermic
b) Endothermic
c) Both (a) and (b)
d) None of the above
Answer:
a) Exothermic

Question 12.
Multi molecular layers are formed in
a) Absorption
b) Physisorption
c) Chemisorption
d) None of the above
Answer:
b) Physisorption

Question 13.
The rate constant of a reaction at temperature 200K is 10 times less than the rate constant at 400K. What is the activation energy of the reaction? (R=gas constant)
a) 1842.4R
b) 921.2 R
c) 460.6 R
d) 230.3 R
Answer:
b) 921.2 R

Question 14.
In adsorption isobar the amount of adsorption is plotted against
a) Pressure
b) Temperature
c) Volume
d) Mass
Answer:
b) Temperature

Question 15.
In physical adsorption isobar x /m, …………………………. with increase in temperature.
a) Increases
b)Decreases
c) First increases then decreases
d) Does not change
Answer:
b) Decreases

Question 16.
In chemisorption isobar x /m …………….. with increase in temperature.
a) Increases
b)Decreases
c) First increases then decreases
d) Does not change
Answer:
c) First increases then decreases

Question 17.
Which of the following is not an equation for Freundlich isotherm?

Answer:
d

Question 18.
Sugar prepared from molasses in decolourised by adding.
a) Silica gel
b) Permutit
c) Animal Charcoal
d) Activated charcoal
Answer:
c) Animal Charcoal

Question 19.
Which of the following is not an application of adsorption?
a) Heterogeneous catalysis
b) Gas masks
c) Froth floatation process
d) Softening of water by boiling
Answer:
d) Softening of water by boiling

Question 20.
The change of W/O emulsion into O/W emulsion is called …………..
a) Coagulation
b) Emulsification
c) Decomposition
d) Invension of phase
Answer:
d) Invension of phase

Question 21.
2SO₂ + O₂ + [NO] → 2SO₃ + [NO] is an example for
a) Positive catalysis
b) Negative catalysis
c) Homogeneous catalysis
d) Both (a) and (c)
Answer:
d) Both (a) and (c)

Question 22.
Which is not a heterogeneous catalysis?
a) Contact process
b) Haber’s process
c) Ester hydrolysis
d) Ostwald’s process
Answer:
c) Ester hydrolysis

Question 23.
Intermediate compound formation theory explains.
a) Homogeneous catalysis
b) Heterogeneous catalysis
c) Autocatalysis
d) Negative catalysis
Answer:
a) Homogeneous catalysis

Question 24.
In intermediate compound formation, the intermediate complex formed has
a) More activation energy than uncatalysed complex
b) Less activation energy than uncatalysed complex
c) Less kinetic energy than the reactants
d) Less kinetic energy than the products
Answer:
b) Less activation energy than uncatalysed complex

Question 25.
Adsorption theory explains
a) Homogeneous catalysis
b) Heterogeneous catalysis
c) Autocatalysis
d) Negative catalysis
Answer:
b) Heterogeneous catalysis

Question 26.
The catalytic activity of a catalyst is increased by a promoter by
a) Increasing the number of active centres
b) Decreasing the number of active centres.
c) Blocking the number of active centres
d) Desorbing the active centres
Answer:
a) Increasing the number of active centres

Question 27.
Enzymes are often present as
a) Crystalloids
b) Suspension
c) Colloids
d) True solutions
Answer:
c) Colloids

Question 28.
In the conversion of 1 – chloro octane into 1 – cyano octane, tetra alkyl ammonium cation acts as a
a) Enzyme catalyst
b) Phase transfer catalyst
c) Zeolite catalyst
d) Nano catalyst
Answer:
b) Phase transfer catalyst

Question 29.
Which of the following is incorrect
a) Enzymes can be inhibited (poisoned)
b) Calalytic activity of enzymes is decreased by coenzvmes.
c) Enzyme catalysis is highly specific in nature
d) the rate of Enzyme catalysed reactions varies with the pH of the system.
Answer:
b) Calalytic activity of enzymes is decreased by coenzymes.

Question 30.
Nano catalysts can act as
a) Homogeneous catalysts
b) Heterogeneous catalysts
c) Phase transfer catalysts
d) Both (a) and (b)
Answer:
d) Both (a) and (b)

Question 31.
Size of colloidal particle is
a) 1 – 200 Å
b) 1 – 200 nm
c) 1 – 200 pm
d) 1 – 200 pm
Answer:
b) 1 – 200 nm

Question 32.
In hydrosols the dispersion medium is
a) Benzene
b) Alcohol
c) Water
d) Ether
Answer:
c) Water

Question 33.
In lyophillic colloids which is true?
a) Definite attractive force exists between the dispersion medium and dispersed phase
b) More stable
c) Reversible sols
d) All the above
Answer:
d) All the above

Question 34.
In lyophobic colloids which is not true?
a) No attractive force exists between the dispersion medium and dispersed phase
b) Less stable
c) Can be produced again
d) Precipitated readily
Answer:
c) Can be produced again

Question 35.
Which among the following is a liquid aerosol?
a) Smoke
b) Fog
c) Shaving cream
d) Froth
Answer:
b) Fog

Question 36.
Which one of the following is negatively charged colloid?
a) arsenic sulphide
b) Ferric hydroxide
c) Haemoglobin
d) Basic dyes
Answer:
a) arsenic sulphide

Question 37.
Butter is a colloid of
In butter the dispersed phase and the
dispersion medium are respectively [222EE3
a) Solid, gas
b) Liquid, solid
c) Solid, liquid
d) Gas, solid
Answer:
c) Solid, liquid

Question 38.
In butter the dispersed phase and the dispersion medium are respectively_______
a) Solid in liquid
b) Liquid in solid
c) Liquid in liquid
d) Liquid in gas
Answer:
b) Liquid in solid

Question 39.
Colloidal graphite can be prepared by
a) Peptisation
b) Mechanical dispersion
c) Ultrasonic dispersion
d) Double decomposition
Answer:
b) Mechanical dispersion

Question 40.
Electro dispersion method is used to prepare the colloidal solution of
a) Copper
b) Silver
c) Gold
d) All the above
Answer:
d) All the above

Question 40.
Arsenic sulphide sol is prepared by the reaction. AS₂O₃ + 3H₂S → As₂S₃ + 3H₂O. This method is known as
a) Hydrolysis
b) Double decomposition
c) Oxidation
d) Reduction
Answer:
b) Double decomposition

Question 42.
Conversion of a colloid into a precipitate is known as
a) Peptisation
b) Dialysis
c) Coagulation
d) Electrophoresis
Answer:
c) Coagulation

Question 43.
Conversion of a precipitate into a colloid is known as
a) Peptisation
b) Dialysis
c) Coagulation
d) Electrophoresis
Answer:
a) Peptisation

Question 43.
The removal of electrolytic impurities from a colloidal solution is known as
a) Peptisation
b) Dialysis
c) Coagulation
d) Electrophoresis
Answer:
b) Dialysis

Question 44.
The movement of dispersed phase under the influence of electric current is known as
a) Electro osmosis
b) Electrophoresis
b) Dialysis
d) Electrophoresis
Answer:
b) Dialysis

Question 45.
The movement of dispersed phase under the influence of electric current is known as
a) Electro osmosis
b) Electrophoresis
c) Electrodialysis
d) Ultra filteration
Answer:
b) Electrophoresis

Question 46.
The movement of dispersion medium under the influence of electric current is known as
a) Electro osmosis
b) Electrophoresis
c) Electrodialysis
d) Ultra filteration
Answer:
a) Electro osmosis

Question 47.
In ultra filteration, ultrafilters are made by using
a) Collodion
b) Cellophane
c) Both (a) and (b)
d) None of the above
Answer:
c) Both (a) & (b)

Question 48.
Collodion is 4% solution of ……………… in a mixture of alcohol and water.
a) Cellulose acetate
c) Chioro cellulose
b) Cellulose sulphate
cl) Nitrocellulose
Answer:
d) Nitrocellulose

Question 49.
Blue colour of the sky. in nature is due to
a) Browniart movement
b) Tyndall effect
c) Both (a) and (b)
d) None of thé above
Answer:
b) Tyndall effect

Question 50.
Scattering of light by colloidal particles is known as
a) Brownian movement
b) Tyndall effect :
c) Electrophoresis
d) Electro osmosis
Answer:
b) Tyndall effect

II. Match the following

Question 1.

Answer:
i) Arsenic in the decomposition of arsine
i) Fe/Pd
ii) Hydrated aluminosilicates
iii) As₂O₃ in contact process
iv) Al₂O₃ in Haber’s process
v) Urease

Question 2.

Answers :
i) Iron
ii) Platinum
iii) Nitric oxide
iv) Cupric chloride
v) Ferric oxide

Question 3.

Answer:
i) Dust
ii) Milk
iii) Paints
iv) Bread
v) Alloys

III. Assertion and Reasoning

Question 1.
Assertion (A) : Physical adsorption occurs at low temperatures.
Reason (R) : The forces of attraction between the adsorbent and adsorbate are weak and heat of adsorption is low
a) Both A and R are correct, R explains A
b) Both A and R are correct, R does not explain A
c) A is correct but R is wrong
d) A is wrong but R is correct.
Answer:
a) Both A and R are correct, R explains A

Question 2.
Assertion (A) : In the reaction CH3COOC2H5 + H20 -> CH3COOH + C2H5OH is an example for autocatalysis.
Reason (R) : One of the product ethanol acts as a catalyst.
a) Both A and R are correct, R explains A
b) Both A and R are correct, R does not explain A
c) A is correct but R is wrong
d) A is wrong but R is correct.
Answer:
c) A is correct but R is wrong.
Correct Reason: One of the product acetic acid acts as a catalyst.

Question 3.
Assertion (A) : 1- Chioro octane is converted into 1 – Cyano octane in I or 2 hours by reacting with sodium cyanide in presence of tetra alkyl ammonium chloride.
Reason (R) : The tetra alkyl ammonium cation transports CN^– from the aqueous phase to the
organic phase using its hydrophilic end.
a) Both A and R are correct, R explains A
h) Both A and R are correct, R does do not explain A
c) A is correct hut R is wrong
d) A is wrong but R is correct.
Answer:
a) Both A and R are correct, R explains A

Question 4.
Assertion (A): Measurements of osmotic pressure is used to find the molecular weight of colloidal particle.
Reason (R): Colloidal solutions show the kinetic property,
a) Both A and R are correct, R explains A
b) Both A and R are correct, R does not explain A
c) A is correct but R is wrong
d) A is wrong but R is correct.
Answer:
b) Both A and R are correct, R does not explain A Correct Reason: Colloidal solutions show colligative properties.

IV. Choose the correct statement

Question 1.
i) Chemisorption is instantaneous
ii) Chemisorption first increases and then decreases with temperature
iii) In chemisorption the heat of adsorption is high
iv) Chemisorption is independent of the surface area of the adsorbent
a) (i) & (ii)
b) (ii) & (iii)
c) (iii) & (iv)
d) (i) & (iv)
Answer:
b) (ii) & (iii)
Correct statement:
Chemisorption is slow,
Chemisorption depends on the surface area of the adsorbent.

Question 2.
i) A catalyst can initiate a reaction
ii) A solid catalyst will be more effective if it is taken in bulk
A catalyst does not affect the position of equilibrium and the value of the equilibrium constant
A catalyst is highly effective at a particular temperature called optimum temperature,
a) (i) & (ii)
b) (ii) & (iii)
c) (iii) & (iv)
d) (i) & (iv)
Answer:
c) (iii) & (iv)

Correct statement:
A catalyst cannot initiate a reaction,
A solid catalyst will be more effective if it is taken in a finely divided form.

Question 3.
i) When light passes through colloidal solution it is scattered in all directions.
ii) When a colloidal solution is observed through ultramicroscope, they showed a random, zigzag, ceaseless motion.
iii) Haemoglobin is a negatively charged colloid
iv) A sol is not electrically neutral.
a) (i) & (ii)
b) (ii) & (iii)
c) (iii) & (iv)
d) (i) & (iv)
Answer:
a) (i) & (ii)

Correct statement: iii) Haemoglobin is a positively charged colloid, iv) A sol is electrically neutral

Question 4.
i) The flocculation and setting down of the sol particles is called coagulation.
ii) The higher the flocculation value greater will be the precipitation.
iii) Lyophilic sols are precipitated readily even with small amount of electrolytes.
iv) When boiled due to increased collisions, the sol particles combine and settle down.
a) (i) & (ii)
b) (ii) & (iii)
c) (iii) & (iv)
d) (i) & (iv)
Answer:
d) (i) & (iv)

Correct statement:
ii) The smaller the flocculation value greater will be the precipitation,
iii) Lyophobic sols are precipitated readily even with small amount of electrolytes

V. Choose the incorrect statement

Question 1.
i) Physisorption decreases with an increase in pressure
ii) Physisorption decreases with an increase in temperature
iii) Activation energy of physisorption is significant
iv) No transfer of electrons occur in physisorption
a) (i) & (ii)
b) (ii) & (iii)
c) (i) & (iii)
d) (iii) & (iv)
Answer:
c) (i) & (iii)

Correct statement:
i) Physisorption increases with increase in pressure,
iii) Activation energy of physisorption is insignificant.

Question 2.
i) Enzyme catalysis is highly specific in nature
ii) The rate of enzyme catalysed reactions does not vary with pH of the system
iii) Catalytic activity of enzymes is decreased by coenzymes.
iv) Enzyme catalysed reaction has maximum rate at optimum temperature.
a) (i) & (ii)
b) (ii) & (iii)
c) (iii) & (iv)
d) (i) & (iv)
Answer:
b) (ii) & (iii)

Correct statement:
ii) The rate of enzyme catalysed reactions varies with pH of the system,
iii) Catalytic activity of enzymes is increased by coenzymes.

Question 3.
i) In zeolites the active sites namely protons are lying inside their pores.
ii) Reactions occur only outside the pores of zeolites.
iii) Bulkier reactant molecules are prevented from reaching the active sites within- the zeolite crystal.
iv) If the transition state of a reaction is large compared to the pore size of the zeolite, then product will be formed.
a) (i) & (ii)
b) (ii) & (iii)
c) (iii) & (iv)
d) (ii) & (iv)
Answer:
d) (ii) & (iv)
Correct statement:
ii) Reactions occur only inside the pores of zeolites,
iv) If the transition state of a reaction is large compared to the pore size of the zeolite, then no product will be formed.

Question 4.
i) Colloidal solutions are heterogeneous in nature having two distinct phases.
ii) Colloidal solutions are unstable and they are affected by gravity.
iii) When the colloidal solution is dilute coagulation occurs.
iv) Unlike true solution, colloids diffuse less readily through membranes.
a) (i) & (ii)
b) (ii) & (iii)
c) (iii) & (iv)
d) (i) & (iv)
Answer:
b) (ii) & (iii)
Correct statement:
ii) Colloidal solutions are quite stable and they are not affected by gravity,
iii) When the colloidal solution is dilute coagulation does not occur

VI. Two Mark Questions

Question 1.
What is adsorption?
Answer:

• Adsorption is a phenomenon of concentration of a substance on the surface of a liquid or gas.
• Adsorption is a surface phenomenon.

Question 2.
What is known as interface?
Answer:
The surface of separation of the two phases where the concentration of adsorbed molecule is high is known as the interface.

Question 3.
What is meant by positive adsorption and negative adsorption?
Answer:
If the concentration of a substance in the interface is high in an adsorption, then it is called positive adsorption. If it is less, then it is called negative adsorption.

Question 4.
What is desorption?
Answer:
The process of removing an adsorbed substance from the surface is called desorption.

Question 5.
What is meant by adsorbent and adsorbate?
Answer:
Absorbent is the material on which adsorption takes place.
Adsorbed substance is called an adsorbate.

Question 6.
Give some examples for adsorbates.
Answer:

• Gaseous molecules like He, Ne, O₂, SO₂ and NH₃
• Solutions of NaCl, KCl

Question 7.
Give some examples for adsorbents.
Answer:
Silica Gel
Metals like Ni, Cu, Pi. Ag and Pd
Certain colloids.

Question 8.
What are the limitations of Freundlich isotherm?
Answer:

• The equation is purely empirical
• Valid over a limited pressure range.
• Constants k and n values vary with temperature and for this no theoretical explanations were given.

Question 9.
How is adsorption principle used in the softening of hard water?
Answer:

• Permutit adsorbs Ca²⁺ and Mg²⁺ ions present in hard water on its surface.
• An ion exchange occurs on its surface. Na₂Al₂Si₄O₁₂ + CaCl₂ → CaAl₂ Si₄ O₁₂ + 2NaCl
• Exhausted permutit is regenerated by adding a solution of common salt.
  CaAl₂ Si₄ O₁₂ + 2NaCl → Na₂Al₂Si₄O₁₂ + CaCl₂

Question 10.
How is ion exchange resins work on the principle of adsorption in demineralising water?
Answer:

• The process is carried out by passing water through two columns of cation and anion exchange resins.
• Cation exchange:
  
• Anion exchange:
  

Question 11.
Define a catalyst.
Answer:
A catalyst is defined as a substance which alters the rate of chemical reaction without itself undergoing chemical change.

Question 12.
What is meant by positive catalysis and negative catalysis?
Answer:

• In positive catalysis the rate of a reaction is increased by the presence of a catalyst.
• In negative catalysis the rate of a reaction is decreased by the presence of a catalyst.

Question 13.
What are promoters?
Answer:

• The substance which increases the activity of a catalyst in a reaction is called promoter.
• (Eg-) In Haber’s process of synthesis of NH₃, MO is the promoter of Fe catalyst.

Question 14.
What are the limitations of intermediate compound formation theory.
Answer:

• Fails to explain the action of catalytic poison and promoters.
• Unable to explain the mechanism of heterogeneous catalysis.

Question 15.
What are active centres?
Answer:

• Surface of a catalyst is not smooth.
• It bears steps, cracks and corners.
• The atoms on such locations are coordinatively unsaturated.
• So they have much residual force of attraction.
• Such sites are called active centres.

Question 16.
What is a colloidal solution?
Answer:
When the diameter of the particles of a substance dispersed in a solvent ranges from 1 – 200 nm, the system is called a colloidal solution.

Question 17.
What is meant by dispersion medium and dispersed phase?
Answer:
In a colloid, the substance present in a larger amount is called dispersion medium and the substance present in less amount is called the dispersed phase.

Question 18.
What is the flocculation value?
Answer:
The precipitation power of electrolyte is determined by finding the minimum concentration(millimoles/lit ) required to cause precipitation of a sol in 2 hours. This value is called flocculation value.
The smaller the flocculation value greater will be precipitation.

Question 19.
Name the dispersion medium present in hydrosol, alcosol and benzosol.
Answer:

Question 20.
How is a colloid prepared by exchange of solvent ?
Answer:

• Colloidal solution of phosphorous or sulphur is obtained by preparing the solutions in alcohol and pouring them into water.
• As they are insoluble in water, they form colloidal solution P in alcohol + water —> P Sol

Question 21.
What is Tyndall effect?
Answer:
The scattering of light by colloidal particles is called Tyndall effect.

Qu

estion 22.
What is Brownian movement?
Answer:

• The random, zigzag, ceaseless motion of colloidal particles in dispersion medium is known as Brownian movement.
• This is due to the continuous bombardment of dispersed phase bv the molecules of dispersion medium.

Question 23.
What is the significance of Brownian movement ?
Answer:

• To calculate Avogadro number.
• To confirm kinetic theory which considers the ceaseless rapid movement of molecules that increases with increase in temperature.
• To understand the stability of colloids.
• As the particles are in continuous rapid movement they do not come close and hence not get condensed. That is Brownian movement does not allow the particles to be acted by force of gravity.

Question 24.
Define ‘gold number’
Answer:

• Gold number is defined as the number of milligrams of hydrophilic colloid that will just prevent the precipitation of 10 ml of gold sol on the addition of 1 ml of 10% NaCl solution.
• Smaller the gold number greater the protective power.

Question 25.
What are emulsions?
Write their types.
Answer:

• Emulsions are colloidal solution in which a liquid is dispersed in another liquid.
• Two types of emulsions are
  (i) Oil in water (O/W)
  (ii) Water in oil (W/ O)

Question 26.
What is emulsification?
Answer:
The process of preparation of emulsion by the dispersal of one liquid in another liquid is called emulsification.

Question 27.
What is de emulsification?
Answer:
The process of separation of an emulsion into two separate layers is called de emulsification.

Question 28.
Write the uses of colloids in medicine?
Answer:

• Antibodies such as penicillin and streptomycin are produced in colloidal form for suitable injections.
• Colloidal gold and colloidal calcium are used as tonics.
• Milk of magnesia is used for stomach troubles.
• Silver sol protected by gelatine known as Argyrol is used as eye lotion.

Question 29.
Mention the shapes of the following colloidal particles,
i) AS₂S₃
ii) Blue gold sol
iii) Tungstic acid sol
Answer:
i) AS₂S₃ -Spherical
ii) Blue gold sol – Disc or plate like
iii) Tungstic acid sol – Rod like

VII. Three Mark Questions

Question 1.
Write the characteristics of adsorption
Answer:

• Adsorption can occur in all interfacial surfaces (ie) between gas-solid, liquid-solid, liquid-liquid, solid-solid, gas-liquid
• Adsorption is always accompanied by decrease in free energy. When ΔG = 0, the equilibrium is attained.
• Adsorption is a spontaneous process.
• Adsorption is accompanied by decrease in randomness (ie) decrease in entropy.
• Adsorption is exothermic.
• Adsorption is a quick process.

Question 2.
Write a note on Freundlich isotherm.
Answer:
A plot between the amount of adsorbate adsorbed and pressure or concentration of adsorhate at constant temperature is called adsorption isotherm.

According to Freundlich x/m = kp^1/n
x = amount of adsorbate
m = mass of adsorbent in gram
p = pressure
k, n = constants, value of n is always less than unity.

This equation is applicable for adsorption of gases on solid surfaces.
For adsorption in solutions of concentration C, the equation is x/m = kC^1/n
These equations quantitatively predict the effect of pressure or concentration on the adsorption of gases or liquids at constant temperature
Taking log

Question 3.
Write a note on (i) auto catalysis , (ii) negative catalysis ?
Answer:
Auto catalysis:
When one of the products formed acts as a catalyst to the reaction it is called as auto catalysis and that product is-called as auto catalyst.
(Eg.) CH₃COOC₂H₅ + H₂O → CH₃COOH + C₂ + C₂H₅OH
Acetic acid acts as the auto catalyst.

Negative catalysis:
When certain substances decreases the rate of the reaction, it is called negative catalysis and the substance is called negative catalyst.
(Eg.) 2H₂O₂ → 2H₂O + O₂
Glycerol acts as a negative catalyst in the above reaction.

Question 4.
What is the role of adsorption in the heterogeneous catalysis.
Answer:
In heterogenous catalysis, the reactants are converted into products only when the reactants are adsorbed on the catalyst surface to form an activated complex which subsequently decomposes to give the product. Hence the role of adsorption is to form activated complex.

Question 5.
Give some examples for enzyme catalysis.
Answer:

Question 6.
Write a note on nano catalysis.
Answer:

• Metallic nano particles, metal oxides are used as catalysts.
• Nano catalysts can act as both homogeneous as well as heterogeneous catalysts.
• Like homogeneous catalysts they give 100% selective transformations and excellent yield and show extremely high activity.
• Like heterogeneous catalysts, they can be recovered and recycled.
• Nano catalysts are actually soluble heterogeneous catalysts.

Question 7.
How can you identify the two types of emulsion.
Answer:

Question 8.
Name some of the de emulsification techniques.
Answer:

• Distilling one component.
• Adding an electrolyte to destroy the charge. Destroying the emulsifier using chemical methods.
• Using solvent extraction to remove one component.
• By freezing one of the components.
• By applying centrifugal force.
• Adding dehydrating agents for water in oil (W/O) type.
• Using ultrasonic waves.
• Heating at high pressure.

VIII. Five Mark Questions

Question 1.
What are the general characteristics of catalysts.
Answer:

• Only a small quantity of catalyst is needed for a reaction.
• There may be some physical changes, but the catalyst remains unchanged’ in mass and its chemical composition.
• A catalyst cannot initiate a reaction, only it speeds up a slow reaction.
• A solid catalyst is more effective in a finely divided form.
• Catalysts are specific in nature.
• A catalyst does not affect the position of equilibrium and the value of equilibrium constant but helps the quick attainment of equilibrium.
• A catalyst is highly effective at a particular temperature called as optimum temperature.
• Presence of a catalyst does not change the nature of products.

Question 2.
What are the special characteristics shown by enzyme catalysed reaction?
Answer:
Effective and efficient conversion An enzyme may transform a million molecules of reactant in a minute. (Eg.) 2H₂O₂ → 2H₂O + O₂

Enzyme catalysis has maximum rate at optimum temperature. The temperature at which the enzymic activity is high or maximum is called as optimum temperature.
Enzymes involved in human body have an optimum temperature 37°C.
The rate of enzyme catalysis varies with pH of the system. The pH at which the rate is maximum is called the optimum pH.
Enzymes can be inhibited or poisoned. Penicillin inhibits the action of bacteria and used for curing diseases like pneumonia, dysentery, cholera.
A small non protein (vitamin) called a coenzyme promotes the catalytic activity of enzyme.

Question 3.
Explain phase transfer catalysis.
Answer:

• If the reactants of a reaction are present in two different solvents which are immiscible, the reaction between them is very slow.
• As the solvents form separate phases, the reactants have to migrate across the boundary to react.
• But migration across the boundary is not easy.
• For such a situation a third solvent miscible with both is added.
• So the phase boundary is eliminated and the reactants mix freely and react fast.
• But for large scale production of any product, use of a third solvent is not convenient as it may be expensive.
• Phase transfer catalysis gives a simple solution for such problems as it avoids the use of solvents.
• Phase transfer catalyst facilitate the transport of a reactant in one solvent to the other solvent where the second reactant is present.
• As the reactants are brought together, they rapidly react and form the product.
  R – Cl + NaCN → R-CN + NaCl
  Organic phase aqueous phase Organic phase aqueous phase
• RC1 = 1 – chloro octane, RCN = 1 – cyano octane
  1- cyano octane is not obtained by directly heating organic phase, 1 – chloro octane ^ with aqueous phase sodium cyanide for^ ’ several days.
• If a small amount of tetra alkyl ammonium chloride is added, 1 – cyano octane occurs in about 100% yield after 1 or 2 hours.
• In this reaction, the tetra alkyl ammonium cation containing hydrophobic and hydrophilic ends, transports CN^– from the aqueous phase to the organic phase using its hydrophilic end.
  
• Both in organic phase Organic phase
  It moves to aqueous phase, releases Cl— again picks up CN^– and transports it.
• So phase transfer catalyst speeds up the reaction by transporting one reactant from one phase to another.

Question 4.
Explain dispersion methods of preparing colloids
Answer:

Mechanical Dispersion:
The solid is ground to colloidal dimension using a colloid mill consists of two metal plates rotating in opposite direction at very high speed of nearlv 7000 revolution / minute.
Required colloidal si/.e is obtained bv adjusting the distance between the two plates.
(Eg.) Colloids of ink and graphite.

ii) Electro Dispersion :
An electric arc is struck between electrodes dispersed in water surrounded by ice.
When a current of l amp/100 v is passed, an arc produced forms vapours of metal which immediate!) condense to form colloidal solution
Alkali hvdroxide is added as an stabilising agent.
(Eg.) Colloids of metals like copper, silver, gold, platinum
Svedberg modified this method for the prepartion of non-aqueous inflammable liquids like pentane, ether and benzene using high frequency alternating current which prevents the decomposition of the liquid.

iii) Ultrasonic Dispersion:
Sound wraves of frequency more than 20 KHz transform coarse suspension to colloids. Claus obtained mercury sol by subjecting mercury to sufficiently high frequency ultrasonic vibrations.
Ultrasonic vibrations produced by generator spread through the oil and transfer the vibration to the vessel with mercury in water.

iv) Peptisation:
Conversion of a precipitate into colloid by the addition of electrolyte is called peptisation.
Added electrolyte is called peptising or dispersing agent.

Question 5.
Explain condensation methods of preparing colloids.
Answer:
i) Oxidation:
Sols of non metals are prepared by this method
HIO₃ + 5HI → 3H₂O + I₂ (sol)

ii) Reduction:
Gold sol is prepared by reducing auric chloride using organic reagent formaldehyde.
2AUCl₃ + 3HCHO + 3H₂ → 2Au (sol) + 6HCl + 3HCOOH

iii) Hydrolysis :
Sols of metal hydroxides are prepared by this method.
FeCl₃ + 3H₂O → Fe(OH)₃ + 3HCl

Double decomposition:
Water insoluble sols are prepared by this method. Yellow coloured arsenic sulphide sol is prepared by passing hydrogen sulphide gas through arsenic oxide.
AS₂O₃+ 3H2S → AS₂S₃ + 3H₂O

vi) Decomposition:

• When a few drops of an acid is added to sodium thio sulphate, it decomposes to form insoluble free sulphur.
• Insoluble free sulphur accumulates into small clusters which impart various colours blue, yellow and even red to the system.
• This colour change is due to their growth within the size of colloidal dimensions.
  

Question 6.
Explain various methods of purification of colloids.

Answer:
Dialysis:

• Colloidal solution is taken in a bag made up of semipermeable membrane.
• It is suspended in a trough of flowing water.
• Electrolytes diffuse out of the membrane and they are carried away by water.

Electro dialysis :

• The presence of electric field increases the speed of removal of electrolytes from colloidal solution.
• Colloidal solution with electrolytic impurity is placed between two dialysing membranes enclosed into two compartments filled with water.
• When current is passed, the impurities pass into water compartment and get removed periodically.
• This process is faster than dialysis, as the rate of diffusion of electrolytes is increased by the application of electricity.

iii) Ultra filtration:

• The pores of ordinary filter papers allow the passage of colloidal particles.
• In ultra filtration the membranes are made by using colloidion, cellophane or visiking.
• When a colloidal solution is filtered using such a filter, colloidial particles are separated on the filter and the impurities are removed as washings.
• This process is quickened by the application of pressure.
• Collodion is 4% solution of nitrocellulose in a mixture of alcohol and water.
• This method of separation of sol particles from electrolyte by filtration through an ultrafilter is called ultrafiltration.

Question 7.
Write a note on Helmholtz double layer.

• The surface of colloidal particle adsorbs one type of ion due to preferential adsorption
• This layer attracts the oppositely charged ions in the medium.
• Hence at the boundary separating the two, electrical double layers are set up.
• This is called as Helmholtz electrical double layer.
• As the particles nearby are having similar charges, they cannot come close and condense.
• This explains the stability of a colloid.

Question 8.
Write a note on electrophoresis.
Answer:

• The migration of sol particles towards an electrode under the influence of electric field is called electrophoresis or cataphoresis.
• When electric potential is applied across two platinum electrodes dipped in a hydrophilic sol, the dispersed particles move toward one or other electrode.
• If the sol particles migrate to the cathode then they possess positive charges.
• If the sol particles migrate to the anode then thev have negative charges.
• Thus from the direction of migration of sol particles, the charge on them can be determined.
• Hence electrophoresis is used for the detection of presence of charges on the sol practicles.

Tamilnadu State Board New Syllabus Samacheer Kalvi 12th Business Maths Guide Pdf Chapter 1 Applications of Matrices and Determinants Ex 1.3 Text Book Back Questions and Answers, Notes.

Tamilnadu Samacheer Kalvi 12th Business Maths Solutions Chapter 1 Applications of Matrices and Determinants Ex 1.3

Question 1.
The subscription of a magazine sends out a letter to a large mailing list inviting subscriptions for the magazine. Some of the people receiving this letter already subscribe to the magazine while others do not. From this mailing list, 45% of those who already subscribe will subscribe again while 30% of those who do not now subscribe will subscribe. On the last letter, it was found that 40% of those receiving it ordered a subscription. What percent of those receiving the current letter can be expected to order a subscription?
Solution:
Transition Probability Matrix

S = 36%; F = 64%
∴ 36% of those receiving the current letter can be expected to order a subscription

Question 2.
Anew transit system has just gone into operation in Chennai. Of those who use the transit system this year, 30% will switch over to using metro train next year and 70% will continue to use he transit system. Of those who use metro train this year and 70% will continue to use metro train next year and 30% will switch over to transit system. Suppose the population of Chennai city remains constant and that 60% of the commuters use the transit system and 40% of the commuters use metro train this year.
(i) What percent of commuters will be using the transit system after one year?
(ii) What percent of commuters will be using the transit system in the one run?
Solution:
Transition Probability Matrix

S = 54%; C = 46%
Equilibrium will be reached in the long run
At equilibrium we must have
(S C) T = (S C) where S + C = 1
(S C) = \(\left(\begin{array}{ll}
0.7 & 0.3 \\
0.3 & 0.7
\end{array}\right)\) = (S C)
0.7S + 0.3C = S
0.7S + 0.3 (1 – S) = S
0.7S + 0.3 – 0.3S = S
0.4S + 0.3 = S
0.3 = S – 0.4S ⇒ 0.6S = 0.3
S = \(\frac { 0.3 }{ 0.6 }\) = 0.50
∴ 50% of the commuters will be transit system the long run.

Question 3.
Two types of soaps A and B are in the market. Their present market shares are 15% for A and 85% for B. Of those who bought A the previous year, 65% contionues to buy it again while 35% switch over to B. Of those who bought B the previous year, 55% buy it again and 45% switch over to A. Find their market shares after one year and when is the equilibrium reached?
Solution:
Transition Probability Matrix

Equilibrium will be reached in the long run
At equilibrium we must have
(A B) T = (A, B) where A + B = 1
(A B) = \(\left(\begin{array}{ll}
0.65 & 0.35 \\
0.45 & 0.55
\end{array}\right)\) = (A B)
0.65 A + 0.45 B = A
0.65 A + 0.45 (1 – A) = A
0.65 A + 0.45 – 0.45 A = A
0.20 A + 0.45 = A
A – 0.20 A = 0.45
0.80 A = 0.45
A = \(\frac { 0.45 }{ 0.80 }\) = 0.5625 and B = 04375
In the long sum {∴ B = 1 – A}
∴ A = 56.25 % and B = 43.75%

Question 4.
Two products A and B currently share the market with shares of 50% and 50% each respectively. Each week some brand switching takes place. Of those who bought A the previous week, 60% buy it again whereas 40% switch over to B. Of those who bought B the previous week, 80% buy it again whereas 20% switch over to A. Find their shares after one week and after two weeks. If the price war continues, when is the equilibrium reached?
Solution:
Transition Probability Matrix

Equilibrium will be reached in the long run.
At equilibrium, we must have
(A B) T = (A B) where A + B = 1
(A B) = \(\left(\begin{array}{ll}
0.60 & 0.40 \\
0.20 & 0.80
\end{array}\right)\) = (A B)
0.60 A + 0.20 B = A
0.60 A+ 0.20 (1 – A) = A
0.60 A + 0.20 – 0.20 A = A
0.40 A + 0.20 = A
0.20 = A – 0.40 A
0.60 A = 0.20
A = \(\frac { 0.20 }{ 0.60 }\) = 0.33 and B = 0.67
{∴ B = 1 – A}
In the long run
∴ A = 33% and B = 67%