Question

Benzenediazonium chloride cannot be stored and is used immediately after its preparation because

• A. it slowly evaporates on storage
• B. it is very unstable and dissociates to give nitrogen
• C. it gets oxidised in air hence cannot be stored
• D. it reacts with all the containers in which it is stored

Answer 1

Answer: (B)

Benzene diazonium chloride cannot be stored and is used immediately after its preparation because it is very unstable with a slight high in temperature and dissociates to give nitrogen.
The diazonium reaction uses nitrous acid to convert phenylamine into the diazonium salt benzene diazonium chloride $\left(C_6{H}_5{N}_2^{+}C{l}^{-}\right)$. Nitrous acid decomposes very readily and so cannot be stored.
The temperature must be kept below $5^{0}C$ in an ice bath during diazotization otherwise the main product decomposes, losing its $N_2$ atoms as $N_2$ gas.