Question

How is the metallic and nonmetallic character of an element related to its electronic configuration?

Answer 1

• The chemical property of any element in the periodic table depends upon its electronic configuration. Therefore, identifying which elements behave as metals and non-metals, depends upon their electronic configuration.

• Metals: Generally, a total of 1 to 3 electrons will be present in the outermost shell or valence of electrons.
• Non-metals: Generally, a total of 4 to 8 electrons will be present in the outermost shell or valence of electrons.

The rules for identifying metals and non-metals are applicable to up to 20 elements. The exception exists for Hydrogen and Helium, as they do not obey such rules. That is, Hydrogen has 1 electron in its outermost shell whereas Helium has 2 electrons and they come in the category of non-metals.

1. Example of a metal:

Sodium $\left(\mathrm{Na}\right)$: The atomic number of Sodium is 11. The electronic configuration contains $K=2,L=8,M=1$. It has 1 electron in its outermost shell.

1. Example of a non-metal:

Carbon $\left(C\right)$: The atomic number of Carbon is 6. The electronic configuration contains $K=2,L=4$. It has 4 electron in its outermost shell.