Molecular-emission spectroscopy in cool flames. Part II. The behaviour of phosphorus-containing compounds

Abstract

A sensitive and selective molecular-emission method for the determination of phosphorus is described, in which the intense green emission obtained by nebulising orthophosphoric acid solution into a cool, nitrogen-hydrogen diffusion flame is measured at 528 mµ. The limit of detection in aqueous solution under the conditions of measurement is 0.1 p.p.m. of phosphorus.

Most cations produce a depressive matrix effect that can be readily overcome by a preliminary ion-exchange separation. Fifty-fold molar excesses of acetic, hydrobromic, hydrochloric, nitric, oxalic, sulphuric and tartaric acids do not interfere.