Extra pure $N_2$ can be obtained by heating :-

What are $X$ and $Y$, respectively in the following reactions?
$Au + \text{aqua regia} \longrightarrow AuCl_4^{-} + H_2O + X$
$Pt + \text{aqua regia} \longrightarrow PtCl_6^{2-} + H_2O + Y$

Two oxides of nitrogen,$NO$ and $NO_2$ are allowed to react together at $243 \ K$ to form a coloured compound of nitrogen $(X)$. When compound $(X)$ reacts with water,it yields another compound of nitrogen $(Y)$. The shape of the anion of $(Y)$ molecule is:

When ammonia is passed over heated $CuO$,it is oxidised to

What is the product formed when ammonia reacts with excess chlorine?

Which of the following is a cyclic phosphate?