What does phosphine $(PH_3)$ form when it reacts with acids?

Which oxide of nitrogen is a coloured gas?

What is the product formed when white phosphorus reacts with thionyl chloride $(SOCl_2)$?

$N_2$ forms $NCl_3$,whereas $P$ can form both $PCl_3$ and $PCl_5$. Why?

Cyclic polymetaphosphates have the general formula $(PO_3)_n^{n-}$. Which of the following statements is true for the cyclic trimeric metaphosphate?

What happens when $H_{3}PO_{3}$ is heated?