Methyl nitrile is hydrolyzed to carboxylic acid in the presence of \(H_3O^+\) as catalyst. An intermediate compound \([A]\) is formed during this reaction.

What is not true regarding the compound [B]?

(A) They are higher boiling liquids than aldehydes and ketones due to extensive H-bonding.

(B) They are soluble in benzene

(C) They produce alkane when heated with soda lime

(D) produces \(CO_2\) when treated with \(NaHCO_3\)

Choose the correct answer from the options given below:

(B) only

The correct answer is option 3. (B) only.

Let us break down each statement regarding compound [B], i.e., acetic acid:

(A) They are higher boiling liquids than aldehydes and ketones due to extensive H-bonding: This statement is true. Acetic acid \((CH_3COOH)\) exhibits higher boiling point compared to many aldehydes and ketones of similar molecular weight due to the presence of strong hydrogen bonding between its molecules. The ability of acetic acid molecules to form hydrogen bonds with each other results in stronger intermolecular forces, requiring more energy to break these bonds and hence leading to a higher boiling point.

(B) They are soluble in benzene: This statement is not true. Acetic acid is a polar molecule due to the presence of the carbonyl group (C=O) and the hydroxyl group (OH). Polar molecules tend to dissolve in polar solvents and not in non-polar solvents like benzene. Acetic acid is soluble in polar solvents such as water, ethanol, and acetone because it can form hydrogen bonds with the solvent molecules. However, it does not dissolve readily in benzene.

(C) They produce alkane when heated with soda lime: This statement is  true. When acetic acid is heated with soda lime (a mixture of sodium hydroxide, NaOH, and calcium oxide, CaO), it undergoes a decarboxylation reaction, producing carbon dioxide gas (\(CO_2\)) and sodium acetate which on further reaction with soda lime gives alkane.

(D) Produces \(CO_2\) when treated with \(NaHCO_3\):This statement is true . When acetic acid reacts with sodium bicarbonate (\(NaHCO_3\)), also known as baking soda, it undergoes a neutralization reaction, producing carbon dioxide gas (\(CO_2\)), sodium acetate, and water. The reaction can be represented by the following equation:

\[ \text{CH}_3\text{COOH} + \text{NaHCO}_3 \rightarrow \text{CH}_3\text{COONa} + \text{CO}_2 + \text{H}_2\text{O} \]

This reaction is commonly used in baking to produce carbon dioxide gas, which helps dough rise.

So, option 3. (B) only is the one that is not true regarding acetic acid.