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 precipitation of nickel with dimethylglyoxime remains incomplete. After filtering off the precipitate, the filtrate contains unreacted nickel and dimethylglyoximate ions. Addition of ammonia to this filtrate produces an equivalent quantity of nickel-dimethylglyoximate which is extracted into chloroform and the absorbance of the extract is measured.
S A NAGRA ,A IMTIAZ ,S JAN ,J ANWAR ,
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