The Polarographic Determination of Phosphate

A method is described for estimating polarographically the amountof phosphate in small volumes of liquid, where the phosphoruscontent lies between 0.5 and 10.5 µg. P/ml. with an errorof ± 0.2 µg. P/ml. even when chloride, nitrate,and sulphate are present in excess. The method is based on precipitationof uranyl phosphate from uranyl acetate and estimation of theuranyl ion left in solution. A comparison is made with the colorimetric method of Berenblumand Chain.