Question

Which is the correct order of second ionization potential of C, N, O and F in the following?

Options

• O > N > F > C

• O > F > N > C

• F > O > N > C

• C > N > O > F

Answer 1

O > F > N > C

Explanation:

The second ionization potential means removal of electron from cation

C⁺ = 1s² 2s² 2p¹, N⁺ = 1s² 2s² 2p²

O⁺ = 1s² 2s² 2p³, F⁺ = 1s² 2s² 2p⁴ 

Therefore O > F > N > C