Benzoyl chloride is prepared from benzoic acid by:

Identify product $C$ in the following conversion sequence: $m$-Hydroxybenzaldehyde $\xrightarrow[\text{Protection of } -OH \text{ group}]{C_6H_5CH_2Cl} A$ $\xrightarrow{[O]} B$ $\xrightarrow{\text{deprotection}} C$.

Hydrolysis of $CH_3CH_2NO_2$ with $85\%$ $H_2SO_4$ gives

In the presence of air,the fermentation of ethyl alcohol by $Acetobacter$ $aceti$ bacteria forms:

The major product in the following reaction is:

Acetic acid is obtained when: