Question

Which of the following ions will NOT have an noble gas configuration?

Options

• S^2–

• Li⁺

• Al³⁺

• O^–

Answer 1

O^– 

Explanation:

2 Noble gas configuration is ns² np⁶ or 1s²

The provided ions' outer electronic configuration is as follows:

S^2– = 3s² 3p⁶, Li+ = 1s², Al³⁺ = 2s² 2p⁶

O^– = 2s² 2p⁵