PUC Science 2nd PUC Class 12 - Karnataka Board PUC Question Bank Solutions for Chemistry

Give the structure of A, B and C in the following reaction:

\[\ce{CH3CH2Br ->[KCN] A ->[LiAlH4] B ->[HNO2][0^\circ C] C}\]

Give the structure of A, B and C in the following reaction:

\[\ce{C6H5NO2 ->[Fe/HCl] A ->[NaNO2 + HCl][273 K] B ->[H2O/H+][\Delta] C}\]

Give the structures of A, B and C in the following reaction:

\[\ce{CH3COOH ->[NH3][\Delta] A ->[NaOBr] B ->[NaNO2/HCl] C}\]

Give the structures of A, B and C in the following reaction:

\[\ce{C6H5NO2 ->[Fe/HCl] A ->[HNO2][273 K] B ->[C6H5OH] C}\]

Why cannot aromatic primary amines be prepared by Gabriel phthalimide synthesis?

Write the reaction of aromatic primary amine with nitrous acid.

Write the reaction of aliphatic primary amine with nitrous acid.

Give a plausible explanation for the following:

Why are amines less acidic than alcohols of comparable molecular masses?

Arrange the following compounds in increasing order of their boiling points.

CH₃CHO, CH₃CH₂OH, CH₃OCH₃, CH₃CH₂CH₃

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?

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

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

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

Write the mechanism of hydration of ethene to yield ethanol.

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

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?

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