Oxides of nitrogen and sulphur form ___ when they react with water vapour present in atmosphere.
acids
Oxides of nitrogen and sulphur form acids when they react with water vapour present in the atmosphere. Nitrogen dioxide forms nitric acid whereas sulphur dioxide forms sulphuric acid on reaction with water vapour. Their presence in rain turns it acidic and this is known as the 'acid rain'. Acid rains can disfigure buildings and plants.