− | Chloride is the '''ionised form of the element chlorine''' and is the principal anion (negative ion) in extracellular fluids, where it is usually combined with the sodium cation (positive ion) to form sodium chloride (common salt). The approximate concentration of salt in blood is 0.9%. | + | Chloride is the '''ionised form of the element chlorine''' and is the principal anion (negative ion) in extracellular fluids, where it is usually combined with the [[Sodium - Nutrition|sodium]] cation (positive ion) to form sodium chloride (common salt). The approximate concentration of salt in blood is 0.9%. |