Alcohols, Phenols and Ethers

Q1 FREE PREVIEW

PYQ

The difference in the reaction of phenol with bromine in chloroform and bromine in water medium is due to [JEE Main 2022, 26 Jul (Shift 1)]

aHyperconujugation in substrate

bPolarity of solvent

cFree radical formation

dElectromeric effect of the substrate

✓ Correct answer: b) Polarity of solvent

ExplanationThe difference in phenol’s reaction with bromine in chloroform vs. water is due to the polarity of the solvent.In water (polar), phenol ionizes to phenoxide, which is highly reactive and gives tribromo product.In chloroform (non-polar), less ionization occurs, giving monobromo product.Correct answer: Option B – Polarity of solvent.

Q2 FREE PREVIEW

PYQ

Which of the following ether react with HBr to form phenol?

(PYQ-2025)

a

\(\mathrm{Ph}-{\mathrm{CH}}_{2}-\mathrm{O}-{\mathrm{CH}}_{2}-{\mathrm{CH}}_{3}\)

b

\(\mathrm{Ph}-{\mathrm{CH}}_{2}-{\mathrm{OCH}}_{3}\)

c

\(\\ {\mathrm{CH}}_{3}\\ \mathrm{Ph}-\mathrm{O}-\overset{|}{\underset{|}{\mathrm{C}}}-{\mathrm{CH}}_{3}\\ {\mathrm{CH}}_{3}\)

d

\(\mathrm{Ph}-{\mathrm{CH}}_{2}-\mathrm{O}-{\mathrm{CH}}_{2}-\mathrm{Ph}\)

✓ Correct answer: c)

\(\\ {\mathrm{CH}}_{3}\\ \mathrm{Ph}-\mathrm{O}-\overset{|}{\underset{|}{\mathrm{C}}}-{\mathrm{CH}}_{3}\\ {\mathrm{CH}}_{3}\)

Explanation

The ether that reacts with HBr to form phenol must have a phenyl (-Ph) group directly attached to oxygen, making cleavage difficult via SN1 or SN2 .

Option C (Ph-O-C(CH₃)₃) forms phenol due to cleavage at the C-O bond.

Q3

PYQ

An unknown alcohol is treated with ”Lucas reagent” to determine whether the alcohol is primary, secondary, or tertiary. Which alcohol reacts fastest and by what mechanism?

a

Secondary alcohol by \(S{N}^{1}\)

b

Tertiary alcohol by \(S{N}^{1}\)

c

Secondary alcohol by \(S{N}^{2}\)

d

Tertiary alcohol by \(S{N}^{2}\)

🔒

Answer & explanation — PYQ Pass

Options are free to see. Unlock the correct answer and full explanation with Pass.

Unlock · ₹149

Q4

PYQ

Given below are two statements : one is labelled as Assertion A and the other is labelled as Reason R

Assertion A : Aryl halides cannot be prepared by replacement of hydroxyl group of phenol by halogen atom.

Reason R : Phenols react with halogen acids violently.

In the light of the above statements, choose the most appropriate answer from the options given below

a

Both \(\mathbf{A}\) and \(\mathbf{R}\) are true and \(\mathbf{R}\) is the correct explanation of \(\mathbf{A}\)

b

Both \(\mathbf{A}\) and \(\mathbf{R}\) are true but \(\mathbf{R}\) is NOT the correct explanation of \(\mathbf{A}\)

c

\(\mathbf{A}\) is false but \(\mathbf{R}\) is true

d

\(\mathbf{A}\) is true but \(\mathbf{R}\) is false

🔒

Answer & explanation — PYQ Pass

Options are free to see. Unlock the correct answer and full explanation with Pass.

Unlock · ₹149

Q5

PYQ

Given below are two statements : one is labelled as Assertion A and the other is labelled as Reason R

Assertion A : Aryl halides cannot be prepared by replacement of hydroxyl group of phenol by halogen atom.

Reason R : Phenols react with halogen acids violently.

In the light of the above statements, choose the most appropriate answer from the options given below

a

Both \(\mathbf{A}\) and \(\mathbf{R}\) are true and \(\mathbf{R}\) is the correct explanation of \(\mathbf{A}\)

b

Both \(\mathbf{A}\) and \(\mathbf{R}\) are true but \(\mathbf{R}\) is NOT the correct explanation of \(\mathbf{A}\)

c

\(\mathbf{A}\) is false but \(\mathbf{R}\) is true

d

\(\mathbf{A}\) is true but \(\mathbf{R}\) is false

🔒

Answer & explanation — PYQ Pass

Options are free to see. Unlock the correct answer and full explanation with Pass.

Unlock · ₹149

Q6

PYQ

Phenolic group can be identified by a positive:

[JEE Main 2024, 27 Jan (Shift 2)]

a

Phthalein dye test

b

Lucas test

c

Tollen's test

d

Carbylamine test

🔒

Answer & explanation — PYQ Pass

Options are free to see. Unlock the correct answer and full explanation with Pass.

Unlock · ₹149

Q7

PYQ

An unknown alcohol is treated with ”Lucas reagent” to determine whether the alcohol is primary, secondary, or tertiary. Which alcohol reacts fastest and by what mechanism?

a

Secondary alcohol by \(S{N}^{1}\)

b

Tertiary alcohol by \(S{N}^{1}\)

c

Secondary alcohol by \(S{N}^{2}\)

d

Tertiary alcohol by \(S{N}^{2}\)

🔒

Answer & explanation — PYQ Pass

Options are free to see. Unlock the correct answer and full explanation with Pass.

Unlock · ₹149

Q8

PYQ

Given below are two statements

Statement-I: The boiling points of alcohols and phenols increase with increase in number of carbon atoms

Statement-II: The boiling points of alcohols and phenols are higher in comparison to other class of compounds such as ethers, haloalkanes

In the light of above statements, choose the correct answer from options given below.

[JEE Main 2025, 23 Jan (Shift 2)]

a

Statement-I is true but statement-II is false

b

Both statement-I and statement-II are true

c

Statement-I is false but statement-II is true

d

Both statement-I and statement-II are false

🔒

Answer & explanation — PYQ Pass

Options are free to see. Unlock the correct answer and full explanation with Pass.

Unlock · ₹149

Q9

PYQ

Given below are two statements: Assertion and Reason

Assertion :- Bromination of phenol in the solvent with low polarity such as \(CHC{l}_{3}\) or \(C{S}_{2}\) requires Lewis acid catalyst.

Reason :- The Lewis acid catalyst polarises the bromine to generate \(B{r}^{+}\)

In the light of the above statements, choose the correct answer from the options given below

[JEE Main 2024, 5 Apr (Shift 1)]

a

Assertion is true but Reason is false

b

Both Assertion and Reason are true

c

Both Assertion and Reason are false

d

Assertion is false but Reason is true

🔒

Answer & explanation — PYQ Pass

Options are free to see. Unlock the correct answer and full explanation with Pass.

Unlock · ₹149

Q10

PYQ

Given below are two statements :
Statement I : Dimethyl ether is completely soluble in water. However, diethyl ether is soluble in water to a very small extent.
Statement II : Sodium metal can be used to dry diethyl ether and not ethyl alcohol.
In the light of given statements, choose the correct answer from the options given below

[JEE Main 2025, 7 Apr (Shift 1)]

a

Statement I is false but Statement II is true

b

Both Statement I and Statement II are false

c

Statement I is true but Statement II is false

d

Both Statement I and Statement II are true

🔒

Answer & explanation — PYQ Pass

Options are free to see. Unlock the correct answer and full explanation with Pass.

Unlock · ₹149

Q11

PYQ

Phenolic group can be identified by a positive:

a

Phthalein dye test

b

Lucas test

c

Tollen's test

d

Carbylamine test

🔒

Answer & explanation — PYQ Pass

Options are free to see. Unlock the correct answer and full explanation with Pass.

Unlock · ₹149

Q12

PYQ

Which of the following ether react with HBr to form phenol?

(PYQ-2025)

a

\(\mathrm{Ph}-{\mathrm{CH}}_{2}-\mathrm{O}-{\mathrm{CH}}_{2}-{\mathrm{CH}}_{3}\)

b

\(\mathrm{Ph}-{\mathrm{CH}}_{2}-{\mathrm{OCH}}_{3}\)

c

\(\\ {\mathrm{CH}}_{3}\\ \mathrm{Ph}-\mathrm{O}-\overset{|}{\underset{|}{\mathrm{C}}}-{\mathrm{CH}}_{3}\\ {\mathrm{CH}}_{3}\)

d

\(\mathrm{Ph}-{\mathrm{CH}}_{2}-\mathrm{O}-{\mathrm{CH}}_{2}-\mathrm{Ph}\)

🔒

Answer & explanation — PYQ Pass

Options are free to see. Unlock the correct answer and full explanation with Pass.

Unlock · ₹149

Q13

PYQ

What is the rate of reaction of releasing carbon dioxide gas with aqueous sodium bicarbonate among the following? (memory based jee mains shift-1 28/01/2025)

(1) Picric acid

(2) Benzoic acid

(3) o-toluic acid

a

1 > 2 > 3

b

3 > 2 > 1

c

1 > 3 > 2

d

2 > 3 > 1

🔒

Answer & explanation — PYQ Pass

Options are free to see. Unlock the correct answer and full explanation with Pass.

Unlock · ₹149

Q14

PYQ

Given below are two statements

Statement-I: The boiling points of alcohols and phenols increase with increase in number of carbon atoms

Statement-II: The boiling points of alcohols and phenols are higher in comparison to other class of compounds such as ethers, haloalkanes

In the light of above statements, choose the correct answer from options given below

[JEE Main 2025, 23 Jan (Shift 2)]

a

Statement-I is true but statement-II is false

b

Both statement-I and statement-II are true

c

Statement-I is false but statement-II is true

d

Both statement-I and statement-II are false

🔒

Answer & explanation — PYQ Pass

Options are free to see. Unlock the correct answer and full explanation with Pass.

Unlock · ₹149

Q15

PYQ

Given below are two statements :
Statement I : Dimethyl ether is completely soluble in water. However, diethyl ether is soluble in water to a very small extent.
Statement II : Sodium metal can be used to dry diethyl ether and not ethyl alcohol.
In the light of given statements, choose the correct answer from the options given below

a

Statement I is false but Statement II is true

b

Both Statement I and Statement II are false

c

Statement I is true but Statement II is false

d

Both Statement I and Statement II are true

🔒

Answer & explanation — PYQ Pass

Options are free to see. Unlock the correct answer and full explanation with Pass.

Unlock · ₹149

Q16

PYQ

Incorrect method of preparation for alcohols from the following is:
[JEE Main 2023, 10 Apr (Shift 2)]

a

Ozonolysis of alkene.

b

Reaction of Ketone with RMgBr followed by hydrolysis.

c

Hydroboration-oxidation of alkene.

d

Reaction of alkyl halide with aqueous \(\mathrm{NaOH}\).

🔒

Answer & explanation — PYQ Pass

Options are free to see. Unlock the correct answer and full explanation with Pass.

Unlock · ₹149

Q17

PYQ

Given below are two statements :
Statement (I): p-nitrophenol is more acidic than m-nitrophenol and o-nitrophenol.
Statement (II): Ethanol will give immediate turbidity with Lucas reagent.
In the light of the above statements, choose the correct answer from the options given below :

a

Statement I is false but Statement II is true

b

Both Statement I and Statement II are false

c

Both Statement I and Statement II are true

d

Statement I is true but Statement II is false

🔒

Answer & explanation — PYQ Pass

Options are free to see. Unlock the correct answer and full explanation with Pass.

Unlock · ₹149

Q18

PYQ

Number of isomeric compounds with molecular formula \({\mathrm{C}}_{9}{\mathrm{H}}_{10}\mathrm{O}\) which (i) do not dissolve in \(\mathrm{NaOH}\) (ii) do not dissolve in \(\mathrm{HCl}\). (iii) do not give orange precipitate with 2 , 4 - DNP (iv) on hydrogenation give identical compound with molecular formula \({\mathrm{C}}_{9}{\mathrm{H}}_{12}\mathrm{O}\) is................
[JEE Main 2023, 1 Feb (Shift 1)]

a

1

b

2

c

3

d

4

🔒

Answer & explanation — PYQ Pass

Options are free to see. Unlock the correct answer and full explanation with Pass.

Unlock · ₹149

Q19

PYQ

Given below are two statements.

Statement I: C₂H₅OH and AgCN both can generate nucleophile.

Statement II: KCN and AgCN both will generate nitrile nucleophile with all reaction conditions.

Choose the most appropriate option

a

Statement I is true but statement II is false

b

Both statement I and II are true

c

Statement I is false but statement II is true

d

Both Statement I and II are false

🔒

Answer & explanation — PYQ Pass

Options are free to see. Unlock the correct answer and full explanation with Pass.

Unlock · ₹149

Q20

PYQ

Assertion (A): Butan -1- ol has higher boiling point than ethoxyethane.

Reason (R): Extensive hydrogen bonding leads to stronger association of molecules.

In the light of the above statements, choose the correct answer from the options given below:

[JEE Main 2023, 8 Apr (Shift 1)]

a

Both (A) and (R) are true and (R) is the correct explanation of (A)

b

(A) is true but R is false

c

Both (A) and (R) are true but (R) is not the correct explanation of (A)

d

(A) is false but (R) is true

🔒

Answer & explanation — PYQ Pass

Options are free to see. Unlock the correct answer and full explanation with Pass.

Unlock · ₹149

Q21

PYQ

Incorrect method of preparation for alcohols from the following is:

a

Ozonolysis of alkene.

b

Reaction of ketone with RMgBr followed by hydrolysis.

c

Hydroboration-oxidation of alkene.

d

Reaction of alkyl halide with aqueous NaOH

🔒

Answer & explanation — PYQ Pass

Options are free to see. Unlock the correct answer and full explanation with Pass.

Unlock · ₹149

Practice more JEE Chemistry PYQs