Magnesium in Sea Water: An Electrode Measurement

Magnesium ion in standard I.A.P.O. sea water was measured with a magnesium-sensitive electrode. The results, presented either as magnesiumion activity (0.017) or as the amount of ionized magnesium (0.048M or about 90 percent of the total magnesium), agree well with the data from the chemical model for sea water proprosed by Garrels and Thompson.