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Answer the following.
Two students Rehan and Ananya were given the same compound, alkyl halide ( ) by their chemistry…
Two students Rehan and Ananya were given the same compound, alkyl halide ($\mathrm{C_2H_5Cl}$) by their chemistry teacher and asked to perform different reactions.
1. Rehan was instructed to use alcoholic KCN as a reagent and Ananya was instructed to use alcoholic AgCN.
2. Rehan observed a compound was formed that could be converted to a carboxylic acid on hydrolysis but Ananya could not obtain the same acid.
3. The teacher explained that the difference was due to the bonding behaviour of cyanide ions in the reagents.
Write the chemical equations of the reactions carried out by Rehan and Ananya.
Answer
Answer
Official answer keyEquations: $\mathrm{C_{2}H_{5}Cl} + \mathrm{KCN} \xrightarrow{\text{alcoholic}\text{,}\text{ }\text{heat}} \mathrm{C_{2}H_{5}CN} + \mathrm{KCl}$ $\mathrm{C_{2}H_{5}Cl} + \mathrm{AgCN} \xrightarrow{\text{alcoholic}\text{,}\text{ }\text{heat}} \mathrm{C_{2}H_{5}NC} + \mathrm{AgCl}$
Products: propanenitrile, isocyanoethane
Rehan (alcoholic KCN) obtains propanenitrile (ethyl cyanide), which on hydrolysis gives propanoic acid. Ananya (alcoholic AgCN) obtains isocyanoethane (ethyl isocyanide, ethyl carbylamine), which does not give the acid.
From ISC 2027 Specimen Chemistry Paper 1, question 12(i).