Question #678ec

1 Answer
Mar 2, 2017

Answer:

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#.
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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).