CONTRIBUTIONS FROM THE CHEMICAL LABORATORY 

 OF HARVARD COLLEGE. 



THE QUANTITATIVE DETERMINATION OF ANTIMONY BY 

 THE GUTZEIT METHOD. 



By Charles Robert Sanger and Emile Raymond Riegel. 



Presented August 31, 1909. Received August 31, 1609. 



The application of the so-called Gutzeit reactions to the quantitative 

 determination of arsenic has been studied by Sanger and Black 1 , who 

 were able to use the general method of Gutzeit 2 for the convenient and 

 reasonably accurate estimation of small amounts of arsenic. In study- 

 ing the interference of the hydrides of sulphur, phosphorus, and anti- 

 mony with the reaction of arsine on paper sensitized with mercuric 

 chloride, the possibility of the quantitative determination of antimony 

 by this method was apparent. 



The action of stibine on mercuric chloride was first investigated by 

 Franceschi 3 , who obtained a white body, to which he gave the formula 

 SbHHg 2 Cl 2 , analogous to the red compound formed by the action of 

 arsine on mercuric chloride. This substance decomposes easily in 

 moist air, turning dark, probably from the separation of mercury. 

 When stibine is allowed to act upon sensitized mercuric chloride paper, 

 as shown by Sanger and Black 1 , no color is given to the strip from 

 amounts of antimonious oxide up to about 70 micromilligrams (mmg.). 

 Hydrochloric acid develops no color. But if the strip is treated with 

 ammonia, a black band ensues, the length and intensity of which are 

 proportional to the amount of antimonious oxide present. On this re- 

 action we have based the following method for the determination of 

 small amounts of antimony. 



1 These Proceedings, 43, 297 (1907); Jour. Soc. Chem. Ind., 26, 1115 

 (1907); Zeitsch. f. anorg. Chem., 58, 121 (1907); Suppl. ann. enciclop. chim., 

 24, 372 (1907-08). 



2 Pharm. Zeitung, 24, 263 (1879). In the original Gutzeit method, the 

 evolved arsine was allowed to act upon paper containing argentic nitrate. 

 From Fliickiger in 1889 (Archiv d. Pharm., 227, 1) came the suggestion of 

 using mercuric chloride. 



3 L'Orosi, 13, 397 (1890). 



