Question

Benzene diazonium chloride reacts with hypophosphorous acid to produce:
(a) phenol
(b) benzene
(c) p-hydroxyazobenzene
(d) benzonitrile

Answer 1

The answer is (b).

Benzene will be formed on the reaction of benzene diazonium chloride with hypophosphoric acid.

Answer 2

Benzene diazonium chloride on reaction with hypophosphorous acid produces benzene:

• Benzene diazonium chloride is also known as a diazonium salt and has the formula:  ArN₂⁺Cl⁻
• Hypophosphorous acid has the formula: H₃PO₂
• When these two compounds react in the presence of water it results in the formation of benzene along with nitrogen, phosphorous acid, and hydrochloric acid.
• The reaction is given as follows:

          ArN₂⁺Cl⁻ + H₃PO₂ + H₂O → ArH (Benzene) + N₂ + H₃PO₃ + HCl

Thus, the reaction of benzene diazonium chloride with hypophosphorous acid produces (Option b) benzene