- Ion: An atom which has more or less electrons than what are a neutral atom.
- Video: Tyler DeWitt - What is an Ion?
- Neutral atoms have the same number of electrons as protons.
- Negative electrons cancel out the positive protons to give the atom a neutral charge.
- Atoms which gain or lose electrons do not have the same number of protons and electrons.
- Anion: More electrons than protons = negative charge
- Cation: More protons than electrons = positive charge
Ions have a charge written in the upper right corner of the atom's symbol to let you know it is different than a neutral atom. Mg+2