Question

$HNO_{2}$ acts as.

• A. Oxidising agent
• B. Reducing agent
• C. Both (1) and (2)
• D. Its solution is stable

Answer 1

Answer: (C)

Both (1) and (2)

Answer 2

Nitrous acid behaves as reducing as well as an oxidising agent. It reduces potassium permanganate, potassium

dichromate, $H_{2}O_{2}$ and other strong oxidising agents. It oxidises strong reducing agents such as hydroiodic acid, sulphurous acid etc.

It oxidises $Fe^{+ 2}$ into $Fe^{+ 3}$ in acidic medium;

$Fe^{+ 2} + HNO_{2} + H^{+} \rightarrow Fe^{+ 3} + NO + H_{2}O$

It reduces acidified $KMnO_{4}$.

$2KMnO_{4} + 3H_{2}SO_{4} + 5HNO_{2} \rightarrow$

$K_{2}SO_{4} + 2MnSO_{4} + 3H_{2}O + 5HNO_{3}$