# How do positive and negative ions form?

Jun 3, 2018

See below.

#### Explanation:

They form through Ionic bonding.

Elements gain or lose electrons to form ions and to gain full outer shells.

For example, let's look at Lithium and Fluorine:

Lithium has $3$ electrons, so it needs to lose one to gain a full outer shell.

Fluorine would gain this electron to have $10$ electrons, giving it $2$ full outer shells.

The Lithium atom would turn into an $L {i}^{+}$ ion with an electronic configuration of $2$, as an electron has a negative charge, losing one would give a positive charge.

The Fluorine atom would change to a ${F}^{-}$ ion with an electronic configuration of $2 , 8$ as it gains a negatively charged subatomic particle, so it turns negative as the atom of an element always has a charge of $0$.

This would form lithium fluoride as a result of this ionic bonding.