Question

Nitrogen has a reasonable oxidation number in all of the following compounds, and
yet one of them is not stable. Which one and why?
i) NF
3 ii) NF
5 iii) HNO
3 iv) NO v) N
2O5

Answer 1

Nitrogen pentafluoride (NF5)is only theoretical compound of nitrogen and fluorine. It cannot be stable because nitrogen pentafluoride also violates the octet rule in which compounds with eight outer shell electrons are particularly stable. Instability of NF5 used to be explained by the lack of d-orbitals on N atom, which makes N formally incapable of making 5 bonds.
Answer: NF5