Question

Question #678ec

Answer 1

Element number 13 has 1 unpaired electron.

Explanation:

Since `Z = 13`, the electronic configuration of this element, which can be obtained using the principle of Aufbau, is `1s^2 2s^2 2p^6 3s^2 3p^1`.

That means that at the last level (the `n = 3` level) there will be two paired electrons in the `3s` orbital and one solitary electron (and, therefore, necessarily unpaired) in one of the `3p` orbitals (in any of them since all three are degenerate).