Types of nitrogen oxides

Oxides of nitrogen provide a fascinating picture from the point of view of their varied structures and diverse chemical behavior. They range from N₂O (oxidation state of nitrogen +1) through NO, N₂O₃, NO₂, N₂O₄ to N₂O₅ in which the oxidation state of nitrogen is from +2 to +5.

Structures of the Oxides of Nitrogen

Preparation of various oxides of nitrogen

is prepared by heating ammonium nitrate. It is collected over hot water.

This gas is known as laughing gas because it causes hysterical laughter.

is prepared by the catalytic oxidation of ammonia at 1100 K in the presence of platinum.

By the action of cold dilute nitric acid on copper turnings.

By the action of sulphuric acid on a mixture of FeSO4 and KNO3 (4:1)

is prepared by cooling equimolar quantities of nitric oxide and nitrogen dioxide to below -20^oC.

By the action of 50% HNO3 on arsenious oxide

is prepared by heating dried lead nitrate in a steel reaction vessel.

It exists in equilibrium with N₂O₄ as:

Above 415 K it contains mainly NO₂ and at 250 K it contains mainly N₂O₄. By heating copper turnings with concentrated HNO₃.

is prepared by dehydrating

concentrated nitric acid with phosphorous pentaoxide.

Uses of oxides of nitrogen

Nitric oxide and nitrogen dioxide are important in the manufacture of nitric acid and nitrate fertilizers. In recent years, N₂O₄ has been used as an oxidizer for rocket fuels in missiles and space vehicles.