P-Block Elements Ques 241
Question: $ HNO_2 $ acts as
[AFMC 1992]
Options:
A) Oxidising agent
B) Reducing agent
C) Both a and b
D) Its solution is stable
Show Answer
Answer:
Correct Answer: C
Solution:
Nitrous acid behaves as reducing as well as an oxidising agent. It reduces potassium permanganate, potassium dichromate, $ H_2O_2 $ and other strong oxidising agents. It oxidises strong reducing agents such as hydroiodic acid, sulphurous acid etc. It oxidises $ F{{e}^{+2}} $ into $ F{{e}^{+3}} $ in acidic medium; $ F{{e}^{+2}}+HNO_2+{{H}^{+}}\to F{{e}^{+3}}+NO+H_2O $ It reduces acidified $ KMnO_4 $ . $ 2KMnO_4+3H_2SO_4+5HNO_2\to $ $ K_2SO_4+2MnSO_4+3H_2O+5HNO_3 $
