oa Agrochemophysica - Determination of calcium in the presence of aluminium, phosphate and sulphate with a filter flamephotometer

Abstract

Different techniques /o r overcoming interference in the flame-photometric determination of calcium were investigated in order to find a suitable procedure for use with an inexpensive filter flame photometer. Aluminium, phosphate and sulphate ions, particularly, interfere with the determination of calcium, and existing methods were not found fully satisfactory for eliminating these interferences. A procedure involving a double precipitation of calcium as the oxalate, was developed and proved completely satisfactory. Reprlicate results were found to agree to within 1 per cent, and a recovery of 99 � 0.5 per cent was obtained.