The general molecular formula which represents the homologous series of alkanols is

1

(a)

\({ C }_{ n }{ H }_{ 2n+2 }O\)

(b)

\({ C }_{ n }{ H }_{ 2n }{ O }_{ 2 }\)

(c)

\({ C }_{ 2 }{ H }_{ 2n }O\)

(d)

\({ C }_{ n }{ H }_{ 2n+1 }O\)

The compound (C) in the following series of reactions is:
\(Aceton+{ CH }_{ 3 }MgBr\overset { Dry\ ether }{ \longrightarrow } A\overset { { H }_{ 3 }{ O }^{ + } }{ \longrightarrow } B\overset { 363K }{ \underset { 20%{ H }_{ 2 }{ SO }_{ 4 } }{ \longrightarrow } } C+H_{ 2 }O\)

1

(a)

2-Methylpropene

(b)

but-2-ene

(c)

but-1-ene

(d)

propene

Phenol reacts with bromine in CS₂ to give

1

(a)

o-bromophenol

(b)

m-bromophenol

(c)

o-and p-bromophenol

(d)

2, 4, 6-tribromophenol

When ethanol is heated with HI and red phosphorus, it gives

1

(a)

ethyl iodide

(b)

ethane

(c)

ethylene

(d)

ether

An ether is more volatile than alcohol having the same molecular formula. This is due to

1

(a)

intermolecular hydrogen bonding in alcohols

(b)

dipolar character of ethers

(c)

alcohols having resonance structures

(d)

intermolecular hydrigen bonding in ethers.

Write the chemical equation for the preparation of phenol from benzene using oleum and sodium hydroxide.

1

(a)

Write the structure of the molecule of a compound whose IUPAC name is 1-phenylpropan-2-ol.

1

(a)

Arrange the following compounds in decreasing order of acidity.
\({ H }_{ 2 }O,ROH,HC\equiv CH\)

1

(a)

\({ H }_{ 2 }O>ROH>HC\equiv CH\)

Explain why low molecular mass alcohols are soluble in water.

1

(a)

It is due to formation of H-bonds with water.

Explain why alcohols and ethers of comparable molecular mass have different boiling points.

1

(a)

It is because alcohol molecules are associated with inter molecular H-bonding, therefore, they have higher boiling point than ethers which are not associated with intermolecular H-bonding due to less polarity.

Describe the mechanism of alcohols reacting both as nucleophiles and as electrophiles in their reactions.

2

(a)

Give IUPAC names of the following compounds:
(i) 

(ii)

(iii)
 
(iv)

2

(a)

Predict the major product of acid catalysed dehydration of 
(i) 1-methyl cyclohexanol, and 
(ii) butan-1-ol

2

(a)

Account the following:
(i) The boiling point of ethanol is higher than that of methanol.
(ii) Phenol is a stronger acid than an alcohol.
(iii) The boiling points of ethers are lower than isomeric alcohols.

3

(a)

Explain the fact that in aryl alkyl ethers,
(i) the alkoxy group activites the benzene ring towards electrophilic substitution and
(ii) it directs the incoming substitutions to ortho and para positions in benzene ring.

3

(a)

Write the mechanism of hydration of ethene to yield ethanol.

3

(a)

2,2-Dimethyloxirane can be cleaved by acid (H⁺).Write its mechanism.

5

(a)

An organic compound (A) with molecular formula C₆H₆O gives a characteristic colour with aqueous FeCl₃ solution. When (A) is treated with CO₂ and NaOH at 410K under pressure, it gives compound (B) which upon acidification gives compound (C). Compound (C) reacts with acetyl chloride to give (D) which is a popular pain killer, Deduce the structures of (A), (B), (C) and (D) and explain all the reactions involved.

5

(a)