The number of oxygen atoms bonded to one phosphorus atom in $P_4O_6$ is

When copper metal is treated with cold and dilute nitric acid,it forms

$Cu +$ conc. $HNO_3$ (hot) $\rightarrow Cu(NO_3)_2 + X$ (oxide of nitrogen);
then $X$ is

$PCl_{5} + P_{4}O_{10} \xrightarrow{\Delta } X$. The product $(X)$ is an oxygen-containing compound. How many moles of an oxyacid are formed on the complete hydrolysis of $1 \text{ mole}$ of $(X)$?

$A$ gas at low temperature does not react with most compounds. It is almost inert and is used to create an inert atmosphere in bulbs. The combustion of this gas is exceptionally an endothermic reaction. Based on the given information,we can conclude that the gas is

Which element of group $-15$ forms the most basic hydride with hydrogen?