Question
Which gas is evolved on heating copper nitrate?
When copper nitrate (Cu(NO3)2) is heated, it undergoes thermal decomposition to produce nitrogen dioxide (NO2), a brown gas, oxygen (O2), and copper(II) oxide (CuO), which is a black solid. The chemical equation for this decomposition reaction is:
2Cu(NO3)2(s) → 2CuO(s) + 4NO2(g) + O2(g)
Nitrogen dioxide is a toxic gas with a characteristic sharp, biting odor and is a significant air pollutant responsible for the reddish-brown color often seen in smog. The oxygen released is a diatomic molecule and is a colorless gas under standard conditions.