Question

On heating blue coloured powder of copper (II) nitrate in a boiling tube, copper
oxide (black), oxygen gas and a brown gas X is formed:
(a) Write a balanced chemical equation of the reaction.
(b) Identity the brown gas X evolved.
(c) Identity the type of reaction.

Answer 1

Answer:

i)

(ii) The brown gas X is nitrogen dioxide, NO2. (1/2)

(iii) Thermal decomposition. (1/2)

(iv) pH< 7

Reason : NO2 dissolves in water to form acidic solution (pH range below 7).