When concentrated nitric acid is heated,it decomposes to give

Correct statements from the following are: $A$. Nitrogen in oxidation states from $+1$ to $+4$ disproportionates in acid medium. $B$. Nitrogen has the ability to form $d\text{--}p$ multiple bonds with itself and other elements with small size and high electronegativity. $C$. $N$-$N$ single bond is stronger than $P$-$P$ single bond. $D$. Nitrogen has highest density in its group due to small size. $E$. The maximum covalency of nitrogen is four since it has only four valence orbitals for bonding.

Ammonia can be dried by

What is the range of oxidation states exhibited by phosphorus?

Which of the following oxides is the anhydride of orthophosphoric acid?

Discuss the reactivity of group-$15$ elements with metals.