The mixed anhydride of nitrogen is

At what temperature is red phosphorus heated to obtain $\alpha$-black phosphorus (in $K$)?

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:

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

Aluminium is usually found in $+3$ oxidation state. In contrast,thallium exists in $+1$ and $+3$ oxidation states. This is due to

The number of $P-O$ bonds in $P_4O_6$ is: