The Micro-Estimation of Sodium, Potassium, Calcium, Magnesium, Chloride, and Sulphate in Sea Water and the Body Fluids of Marine Animals

Abstract

Methods are presented for the estimation of sodium, potassium, calcium, magnesium, chloride and sulphate in sea water and in other solutions, such as the blood and body fluids of marine animals, whose inorganic composition is similar to that of sea water.The estimations may be performed on 1 ml. samples, and the limit of error is about 2 %.Sodium is precipitated and weighed as sodium zinc uranyl acetate ; potassium is precipitated as potassium silver cobaltinitrite which is titrated with ceric sulphate ; calcium is titrated with ceric sulphate after two precipitations as oxalate ; magnesium is precipitated with hydroxyquinoline and the precipitate brominated and estimated iodometrically; chloride is treated with silver iodate and the released iodate estimated iodometrically; sulphate is titrated with barium chloride using sodium rhodizonate as indicator.