Which of the following molecules is stable,does not undergo hydrolysis by water,and has a very low tendency to act as a donor?

Can $PCl_{5}$ act as an oxidizing as well as a reducing agent? Justify.

Which of the following oxides is least acidic?

Given below are two statements:
Statement-$I$: Element '$X$' and '$Y$' are the most and least electronegative elements, respectively, among $N, As, Sb$ and $P$. The nature of the oxides $X_{2}O_{3}$ and $Y_{2}O_{3}$ is acidic and amphoteric, respectively.
Statement-$II$: $BCl_{3}$ is covalent in nature and gets hydrolysed in water. It produces $[B(OH)_{4}]^{-}$ and $HCl$ in aqueous medium.

Write the structure of pyrophosphoric acid.

At high temperatures,nitrogen directly combines with