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An ion is an atom or group of atoms that has an electric charge. Ions with a positive charge are called cations. Ions with a negative charge are called anions.

Many normal substances exist in the body as ions. Common examples include sodium, potassium, calcium, chloride, and bicarbonate. (See: Electrolytes)

Ions can be created using radiation such as x-rays. Ionizing radiation is often used for diagnostic or therapeutic procedures.

Alternative Names

Cations; Anions

Update Date 8/3/2013