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

Which of the following reactions forms $N_2O$?

The correct order of reducing abilities of hydrides of group $15$ elements is:

When phosphine is passed through an aqueous solution of copper sulphate,the product produced is:

Red Phosphorus is chemically less reactive because $:-$

Which among the following oxoacids of phosphorus will have $P-O-P$ bonds?
$I$. $H_4P_2O_5$
$II$. $H_4P_2O_6$
$III$. $H_4P_2O_7$
$IV$. $(HPO_3)_3$