Question

How do you find the oxidation number of nitrogen in these molecules?

`HNO_3`
`N_2H_4`
`NO_2^+`
`N_2`
`NO_2^-`
`NO_2`
`N_2O_4`
`N_2O`
`NO`

Answer 1

`HNO_3` `"Nitrogen +V"`

Explanation:

`N_2H_4,` `"Nitrogen -II"`

`NO_2^+,` `"Nitrogen +V"`

`N_2,` `"Nitrogen 0"`

`NO_2^-,` `"Nitrogen +III"`

`NO_2,` `"Nitrogen +IV"`

`N_2H_4,` `"Nitrogen -II"`

`N_2O,` `"Nitrogen +I"`, `N-=N^(+)-O^(-)`, the terminal nitrogen is zerovalent, and the central `N` is `+II`, i.e. average `+I` state.

`N_2O_4,` `"Nitrogen +IV"`

`NO,` `"Nitrogen +II"`

I think I have got these right. Oxygen is more electronegative than nitrogen so it gets the electric charge in determining oxidation state.