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monium chloride is added. This means that traces of chl'.irides which occur 

 as impurities in so many reagents will not cause trouble by giving tests 

 by this method. Smaller quantities of chlorine may be detected by using 

 more dilute ammonium hydroxide in dissolving the silver chloride. 



Corresponding solutions prepared with silver bromide in place of silver 

 chloride gave no precipitates with ammonium chloride. In every case 

 they produced a turbidity when acidified with nitric acid. 



SUMMARY. 



This paper describes a new method for the qualitative separation and 

 detection of chlorides in the presence of bromides and iodides. 



The mixed silver halids are digested with ammonium hydroxide (10 

 per cent). The filtrate is diluted with 10 volumes of water and treated 

 with a few drops of ammonium chloride solution. ] f silver chloride is 

 present a precipitate is produced. 



This method has the advantages over other methods that: 



1. Bromides do not give any precipitate. 



2. The concentration of the ammonium hydroxide solution is great 

 enough that traces of chlorides occurring as Impurities will not give tests. 

 The method becomes more delicate when more dilute solutions of ammo- 

 nium hydroxide are used. 



Indiana University, Bloomington. 



