Which of the following oxides of nitrogen is paramagnetic?

For $H_3PO_3$ and $H_3PO_4$,the correct choice is:

Phosphorus is manufactured by heating in an electric furnace a mixture of

$PbO_2$ is

White phosphorus is heated with concentrated $NaOH$ in $CO_2$ atmosphere to form a gas $A$ and compound $B$. When $A$ is bubbled into aqueous $CuSO_4$ solution,copper phosphide and $C$ are formed. $B$ and $C$ are respectively:

In the hydrides of the nitrogen group,the $H-M-H$ bond angle gradually approaches $90^o$ as we move from $N$ to $Sb$. This indicates that gradually.....