Question

Among the following , the number of elements showing only one non-zero oxidation state is:
`O,C,F,N,P,Sn,Tl,Na,Ti`

Answer 1

Correct Answer - 2
Only F and `Na` show only one non-zero oxidation state.
`O=O^(-), O^(2-), O^(2+)`,
`Cl = -1` to `+7`
`N = -3` to `5`
`P = -3` to `+5`
`Sn =+2, +4`
`Tl = +1, +3` (rare but does exist)
`Ti = +2, +3, +4`