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Atomic Structure

What happens when a Sodium Atom becomes a Sodium Ion?

A sodium atom has 1 electron in its outer shell.
It is in group 1 of the periodic table.

When sodium reacts with non-metals (for example chlorine) it will
lose its outer electron. Its outer shell will then have no electrons.
It is as though the outer shell has vanished. The next shell in is full.
This full inner shell becomes the new full outer shell.

  The sodium atom loses its outer electron to become a sodium ion.
The sodium ion still has 11 protons (11 positive charges)
but now only 10 electrons (10 negative charges).
The sodium ion has an extra positive charge, shown by the + sign.
All group 1 metals will form a 1+ ion
when they react with non-metals.

The charge on the ion can also be shown as
 
and the electron structure written as [2, 8]⁺

The charge on the sodium ion will make it react and form
ionic bonds with other oppositely charged ions.
The full outer shell of electrons does not make the sodium ion
unreactive (see an example).

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