Which of the following reactions gives nitrogen $(II)$ oxide $(NO)$ as one of the products?

Identify the element for which $+1$ oxidation state is more stable than $+3$ oxidation state.

Which statement is incorrect for nitric oxide $(NO)$?

Determine whether the following statements are True $(T)$ or False $(F)$:
$1.$ Ammonia is produced from a mixture of $SO_2$ and $N_2$.
$2.$ $N_2H_2$ and $N_2H_4$ are formed from a mixture of $N_2/H_2$ in the Haber process.
$3.$ Compounds of $d$ or $f$ block elements are not used as catalysts in the Haber process.

$HNO_3 + P_4O_{10} \rightarrow HPO_3 + A$; the product $A$ is

Of the different allotropes of phosphorus,the one which is most reactive is