NCERT solutions for Chemistry [English] Class 12 chapter 11 - Alcohols, Phenols and Ethers [Latest edition]

Classify the following as primary, secondary and tertiary alcohol:

\[\begin{array}{cc}
\ce{CH3}\phantom{.}\\
|\phantom{....}\\
\ce{CH3 - C - CH2OH}\\
|\phantom{....}\\
\ce{CH3}\phantom{.}
\end{array}\]

Classify the following as primary, secondary and tertiary alcohol:

H₂C = CH – CH₂OH

Classify the following as primary, secondary and tertiary alcohol:

CH₃ – CH₂ – CH₂ – OH 

Classify the following as primary, secondary and tertiary alcohol:

Classify the following as primary, secondary and tertiary alcohol:

Classify the following as primary, secondary and tertiary alcohol:

Identify allylic alcohols in the following examples.

Name the following compound according to IUPAC system.

\[\begin{array}{cc}
\phantom{............}\ce{CH2OH}\\
\phantom{......}|\\
\ce{CH3 - CH2 - CH - CH - CH - CH3}\\
\phantom{......}|\phantom{............}|\phantom{.}\\
\phantom{........}\ce{CH2Cl}\phantom{......}\ce{CH3}\phantom{}
\end{array}\]

Name the following compound according to IUPAC system.

\[\begin{array}{cc}
\phantom{........................}\ce{CH2OH}\\
\phantom{..................}|\\
\ce{CH3 - CH - CH2 - CH - CH - CH3}\\
\phantom{}|\phantom{.............}|\phantom{........}\\
\phantom{..}\ce{CH3}\phantom{..........}\ce{OH}\phantom{........}
\end{array}\]

Name the following compound according to IUPAC system.

Name the following compound according to IUPAC system.

\[\begin{array}{cc}
\ce{H2C = CH - CH - CH2 - CH2 - CH3}\\
|\phantom{..........}\\
\ce{OH}\phantom{........}
\end{array}\]

Name the following compound according to IUPAC system.

\[\begin{array}{cc}
\ce{CH3 - C = C - CH2OH}\\
\phantom{}|\phantom{....}|\phantom{....}\\
\phantom{}\ce{CH3}\phantom{.}\ce{Br}\phantom{...}
\end{array}\]

Show how is the following alcohol prepared by the reaction of a suitable Grignard reagent on methanal?

\[\begin{array}{cc}
\ce{CH3 - CH - CH2OH}\\
|\phantom{......}\\
\ce{CH3}\phantom{...}
\end{array}\]

Show how is the following alcohol prepared by the reaction of a suitable Grignard reagent on methanal?

\[\ce{CH3 - CH = CH2 ->[H2O/H^+]}\]

Write the structure of the product of the following reaction:

Write the structure of the product of the following reaction:

\[\begin{array}{cc}
\ce{CH3 - CH2 - CH - CHO ->[NaBH4]}\\
|\phantom{....}\\
\ce{CH3}\phantom{.}
\end{array}\]

Give the structure of the product you would expect when the following alcohol reacts with HCl–ZnCl₂.

Butan-1-ol

Give the structure of the product you would expect when the following alcohol reacts with HCl–ZnCl₂.

2-Methylbutan-2-ol

Predict the major product of acid catalysed dehydration of 1-methylcyclohexanol.

Predict the major product of acid catalysed dehydration of butan-1-ol.

Ortho and para nitrophenols are more acidic than phenol. Draw the resonance structures of the corresponding phenoxide ions.

Write the equation involved in the following reaction:

Reimer-Tiemann reaction

Write the equation involved in the following reaction:

Kolbe’s reaction

Write the reactions of Williamson synthesis of 2-ethoxy-3-methylpentane starting from ethanol and 3-methylpentan-2-ol.

Which of the following is an appropriate set of reactants for the preparation of 1-methoxy-4-nitrobenzene and why?

(i)	(ii)

Predict the product of the following reaction:

\[\ce{CH3 - CH2 - CH2 - O - CH3 + HBr ->}\]

Predict the product of the following reaction:

Predict the product of the following reaction:

Predict the product of the following reaction:

\[\ce{(CH3)3C - OC2H5 ->[HI]}\]

Write IUPAC name of the following compound:

\[\begin{array}{cc}
\phantom{................}\ce{CH3}\\
\phantom{.............}|\\
\ce{CH3 - CH - CH - C - CH3}\\
|\phantom{......}|\phantom{......}|\\
\phantom{...}\ce{CH3\phantom{.}}\phantom{..}\ce{OH}\phantom{...}\ce{CH3}
\end{array}\]

Write IUPAC name of the following compound:

\[\begin{array}{cc}
\ce{H3C - CH - CH2 - CH - CH - CH2 - CH3}\\
\phantom{}|\phantom{.............}|\phantom{......}|\phantom{.........}\\
\phantom{}\ce{OH}\phantom{..........}\ce{OH}\phantom{...}\ce{C2H5}\phantom{......}
\end{array}\]

Write IUPAC name of the following compound:

\[\begin{array}{cc}
\ce{CH3 - CH - CH - CH3}\\
|\phantom{......}|\phantom{..}\\
\ce{OH}\phantom{...}\ce{OH}\phantom{}
\end{array}\]

Write IUPAC name of the following compound:

\[\begin{array}{cc}
\ce{HO - CH2 - CH - CH2 - OH}\\
|\phantom{..}\\
\ce{OH}
\end{array}\]

Write IUPAC name of the following compound:

Write IUPAC name of the following compound:

Write IUPAC name of the following compound:

Write IUPAC name of the following compound:

Write IUPAC name of the following compound:

\[\begin{array}{cc}
\ce{CH3 - O - CH2 - CH - CH3}\\
\phantom{..........}|\\
\phantom{............}\ce{CH3}
\end{array}\]

Write IUPAC name of the following compound:

C₆H₅ – O – C₂H₅

Write IUPAC name of the following compound:

C₆H₅ – O – C₇H₁₅(n−)

Write IUPAC name of the following compound:

\[\begin{array}{cc}
\ce{CH3 - CH2 - O - CH - CH2 - CH3}\\
\phantom{...}|\\
\phantom{.....}\ce{CH3}
\end{array}\]

Write the structure of the compound whose IUPAC name is as follows:

2-Methylbutan-2-ol

Write structures of the compounds whose IUPAC names are as follows:

3-Chloromethylpentan-1-ol.

Write the structure of the compound whose IUPAC name is as follows:

1-Phenylpropan-2-ol

Write the structure of the compound whose IUPAC name is as follows:

3, 5-Dimethylhexane−1, 3, 5-triol

Write the structure of the compound whose IUPAC name is as follows:

2, 3-Diethylphenol

Write the structure of the compound whose IUPAC name is as follows:

1-Ethoxypropane

Write the structure of the compound whose IUPAC name is as follows:

2-Ethoxy-3-methylpentane

Write the structure of the compound whose IUPAC name is as follows:

Cyclohexylmethanol

Write the structure of the compound whose IUPAC name is as follows:

3-Cyclohexylpentan-3-ol

Write the structure of the compound whose IUPAC name is as follows:

Cyclopent-3-en-1-ol

1. Draw the structures of all isomeric alcohols of molecular formula C₅H₁₂O and give their IUPAC names.
2. Classify the isomers of alcohols in the above question as primary, secondary and tertiary alcohols.

Alcohols are comparatively more soluble in water than hydrocarbons of comparable molecular masses. Explain this fact.

What is meant by hydroboration-oxidation reaction? Illustrate it with an example.

Give the structures and IUPAC names of monohydric phenols of molecular formula C₇H₈O.

While separating a mixture of ortho and para nitrophenols by steam distillation, name the isomer which will be steam volatile. Give reason.

Give the equations of reactions for the preparation of phenol from cumene.

Write chemical reaction for the preparation of phenol from chlorobenzene.

Write the mechanism of hydration of ethene to yield ethanol.

You are given benzene, conc. H₂SO₄ and NaOH. Write the equations for the preparation of phenol using these reagents.

Show how will you synthesize 1-phenylethanol from a suitable alkene.

Show how will you synthesize cyclohexylmethanol using an alkyl halide by an S_N2 reaction.

Show how will you synthesize pentan-1-ol using a suitable alkyl halide.

Give two reactions that show the acidic nature of phenol.

Compare acidity of phenol with that of ethanol.

Give reasons for the following:

o-nitrophenol is more acidic than o-methoxyphenol.

Explain how does the −OH group attached to a carbon of benzene ring activate it towards electrophilic substitution?

Give the equation of the following reaction:

Oxidation of propan-1-ol with alkaline KMnO₄ solution.

Give the equation of the following reaction: 

Bromine in CS₂ with phenol.

Give the equation of the following reaction: 

Dilute HNO₃ with phenol.

Give the equation of the following reaction: 

Treating phenol with chloroform in the presence of aqueous NaOH.

Explain the following with an example.

Kolbe’s reaction.

Write the equation involved in the following reaction:

Reimer-Tiemann reaction

Explain the following with an example.

Williamson ether synthesis

Explain the following with an example.

Unsymmetrical ether

Write the mechanism of acid-catalysed dehydration of ethanol to yield ethene.

How is the following conversion carried out?

\[\ce{Propene -> Propan-2-ol}\]

How is the following conversion carried out?

\[\ce{Benzyl chloride -> Benzyl alcohol}\]

How is the following conversion carried out?

\[\ce{Ethyl magnesium chloride -> Propan-1-ol}\]

How is the following conversion carried out?

\[\ce{Methyl magnesium bromide → 2-Methylpropan-2-ol}\]

Name the reagent used in the following reaction:

Oxidation of a primary alcohol to carboxylic acid.

Name the reagent used in the following reaction:

Oxidation of a primary alcohol to aldehyde.

Name the reagent used in the following reaction:

Bromination of phenol to 2, 4, 6-tribromophenol.

Name the reagent used in the following reaction:

Benzyl alcohol to benzoic acid.

Name the reagent used in the following reaction:

Dehydration of propan-2-ol to propene.

Name the reagent used in the following reaction:

Butan-2-one to butan-2-ol.

Give reason for the higher boiling point of ethanol in comparison to methoxymethane.

Give IUPAC name of the following ether:

\[\begin{array}{cc}
\ce{C2H5OCH2 - CH - CH3}\\
\phantom{.....}|\\
\phantom{.......}\ce{CH3}
\end{array}\]

Give IUPAC name of the following ether:

CH₃OCH₂CH₂Cl

Give IUPAC name of the following ether:

O₂N – C₆H₄ – OCH₃(p)

Write the name of the reagent and equation for the preparation of the following ethers by Williamson’s synthesis:

1-Methoxyethane

Give IUPAC name of the following ether:

Give IUPAC name of the following ether:

Write the name of the reagent and the equation for the preparation of the following ether by Williamson’s synthesis:

1-Propoxypropane

Write the name of the reagent and the equation for the preparation of the following ether by Williamson’s synthesis:

Ethoxybenzene

Write the name of the reagent and the equation for the preparation of the following ether by Williamson’s synthesis:

2-Methoxy-2-methylpropane

Illustrate with examples the limitations of Williamson synthesis for the preparation of certain types of ethers.

How is 1-propoxypropane synthesised from propan-1-ol? Write mechanism of this reaction.

Preparation of ethers by acid dehydration of secondary or tertiary alcohols is not a suitable method. Give reason.

Write the equation of the reaction of hydrogen iodide with 1-propoxypropane.

Write the equation of the reaction of hydrogen iodide with methoxybenzene.

Write the equation of the reaction of hydrogen iodide with benzyl ethyl ether.

Explain the fact that in aryl alkyl ethers 

1. the alkoxy group activates the benzene ring towards electrophilic substitution and
2. it directs the incoming substituents to ortho and para positions in the benzene ring.

Write the mechanism of the reaction of HI with methoxymethane.

Write the equation of the following reaction:

Friedel-Crafts reaction - alkylation of anisole

Write the equation of the following reaction:

Nitration of anisole.

Write the equation of the following reaction:

Bromination of anisole in an ethanoic acid medium.

Write the equation of the following reaction:

Friedel-Craft’s acetylation of anisole.

Show how you would synthesise the following alcohol from an appropriate alkene?

Show how you would synthesise the following alcohol from an appropriate alkene?

Show how you would synthesise the following alcohol from an appropriate alkene?

When 3-methylbutan-2-ol is treated with HBr, the following reaction takes place:

\[\begin{array}{cc}
\phantom{.......................}\ce{Br}\\
\phantom{......................}|\\
\ce{CH3 - CH - CH - CH3 ->[HBr] CH3 - C - CH2 - CH3}\\
\phantom{.}|\phantom{......}|\phantom{......................}|\phantom{........}\\
\phantom{}\ce{CH3}\phantom{...}\ce{OH}\phantom{...................}\ce{CH3}\phantom{.....}
\end{array}\]

Give a mechanism for this reaction.

(Hint: The secondary carbocation formed in step II rearranges to a more

stable tertiary carbocation by a hydride ion shift from 3rd carbon atom.)