A metal (A) on heating in nitrogen gas gives compound B. B on treatment with H2O gives a colourless gas which when passed through CuSO4 solution gives a dark blue-violet coloured solution. A and B respectively, are :

Question

A metal (A) on heating in nitrogen gas gives compound B. B on treatment with H₂O gives a colourless gas which when passed through CuSO₄ solution gives a dark blue-violet coloured solution. A and B respectively, are :

Na and NaNO₃