Determination of phosphorus in phosphazenes and phosphines

An improved technique for the determination of phosphorus in organic phosphazenes and phosphines is described. An acid digestion using a mixture of fuming nitric, sulphuric and perchloric acids converts the organically bound phosphorus into orthophosphate. The orthophosphate is precipitated as magnesium ammonium phosphate, which is ignited to magnesium pyrophosphate. With this technique phosphorus was determined in several compounds. The results establish both good accuracy and precision for the method.