Aldehydes, Ketones and Carboxylic Acids Part 3

Concept:Grignard reagents react with carbon dioxide to form carboxylic acids after hydrolysis.Explanation:Bromobenzene reacts with magnesium in dry ether to form phenylmagnesium bromide ($\mathrm{C_6H_5MgBr}$).This Grignard reagent is then treated with dry carbon dioxide ($\mathrm{CO_2}$).The intermediate complex is hydrolysed with dilute acid to yield benzoic acid ($\mathrm{C_6H_5COOH}$).Product P is therefore benzoic acid.Answer:P is benzoic acid, which corresponds to the option showing the $\mathrm{C_6H_5COOH}$ structure.