Nitrogen

NITROGEN: It occurs mainly as a free element in the air making up about 78% volume of the atmosphere.

Laboratory Preparation of Nitrogen

It is prepared by the decomposition of ammonium dioxinitrate (iii). NB: We combine NaNO 2(aq) AND NH4CL(aq) for the decomposition since direct heating of NH4NO2 is very dangerous.

NaNO_2(aq) + NH₄CL_{(aq)  →}   NH₄NO₂(aq) + NaCL_(aq)

NH₄NO_2(aq)  →  N₂(g) + 2H₂O_(L)

It can also be obtained from the air.

Industrially, it is obtained in the fractional distillation of air.