An organic compound $$X$$ on treatment with PCC in dichloromethane gives the compound $$Y$$. Compound $$Y$$ reacts with $$\mathrm{I}_2$$ and alkali to form yellow precipitate of triiodomethane. The compound $$X$$ is
A compound $$'A' \left(\mathrm{C}_7 \mathrm{H}_8 \mathrm{O}\right)$$ is insoluble in $$\mathrm{NaHCO}_3$$ solution but dissolve in $$\mathrm{NaOH}$$ and give a characteristic colour with neutral $$\mathrm{FeCl}_3$$ solution. When treated with bromine water compound '$$A$$' forms the compound $$B$$ with the formula $$\mathrm{C}_7 \mathrm{H}_5 \mathrm{OBr}_3$$. '$$A$$' is
In set of reactions, identify $$D$$
$$\mathrm{CH}_3 \mathrm{COOH} \xrightarrow{\mathrm{SOCl}_2} A \xrightarrow[\text { Anhy. } \mathrm{AlCl}_3]{\text { Benzene }} B \xrightarrow{\mathrm{HCN}} C \xrightarrow{\mathrm{H}_2 \mathrm{O}} D$$
$$K_a$$ values for acids $$\mathrm{H}_2 \mathrm{SO}_3, \mathrm{HNO}_2, \mathrm{CH}_3 \mathrm{COOH}$$ and $$\mathrm{HCN}$$ are respectively $$13 \times 10^{-2}, 4 \times 10^{-4}, 1.8 \times 10^{-5}$$ and $$4 \times 10^{-10}$$, which of the above acids produces stronger conjugate base in aqueous solution?