An Indirect Spectrophotometric Method for the Microdetermination of Nitrogen (as ammonia)

Abstract

A simple indirect spectrophotometric method for the determination of nitrogen (as ammonia) is described. The method is based on the fact that in a neutral medium the precipi tat ion of nickel with dimethylglyoxime remains incomplete. After filtering off the precipitate, the filtrate contains unreacted nickel and dimethyl glyoximate ions. Addition of armonia to this filtrate produces an equivalent quantity of nickel-dimethyl glyoximate which is extracted into chloroform and the absorbance of the extract is measured.