# Ionization
**Ionization** is any process where electrically neutral atoms/molecules become electrically charged by gaining or losing electrons.
- An [[Atoms and Elements|atom]] is always electrically *neutral*
- An ion is either *positively (cation)* or *negatively (anion)* charged
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### Ionization Energy
Atoms and ions that have the same electron configuration
> **Ionization Energy:** The energy required to remove an electron from an
First Ionization Energy ($IE_1$): A value that is recorded by slowly increasing radiation levels *until a single electron is lost.*
- Decreases across groups
- Increases across periods