﻿ARSENICALS. 



19 



lime soaps, for which reason more arsenic was left in a free or soluble 

 form when acid lead arsenate was used -than when calcium ar enate 

 was used. Based on the results of chemical analyses, both of ll 

 mixtures are incompatible. 



ACID LEAD OR CALCIUM ARSENATES AND NICOTINE SULPHATE 8OLUTION8. 



Mixtures of acid lead arsenate and of calcium arsenate with a 

 solution of nicotine sulphate were prepared and analyzed. A 1-800 

 dilution of a 40 per cent solution of nicotine sulphate was made. In 

 the first series 500 cubic centimeter flasks were filled with this dilute 

 nicotine sulphate solution and 1.2 grams of acid lead arsenate (sample 

 39) or 1 gram of calcium arsenate (sample 57), containing 13 percent 

 of free calcium oxid, was added to each of the flasks, with the ex- 

 ception of the controls. Kesults of the anatyses of the lead and cal- 

 cium arsenates used are given in Table 3. After agitating the differ- 

 ent solutions for periods of one hour, one day, and three days they 

 were immediately filtered and the filtrates were analyzed for arsenic 

 and nicotine. Nicotine was determined by the official silicotungstic 

 acid method (1). A second series of tests, using two commercial 

 calcium arsenate samples (Nos. 32 and 59) and a pure tricalcium 

 arsenate prepared by C. M. Smith, was made. Sample 32 contained 

 9.99 per cent, sample 59, 5.23 per cent, and sample 464 no free calcium 

 oxid. In this series 0.6 gram of the calcium arsenate was placed in 

 each of a series of 300 cubic centimeter flasks, which were made to 

 volume with the dilute nicotine sulphate solution. These solutions 

 were agitated for one hour and for three days. 



Table 9. — Results of combining acid lead arsenate or calcium arsenate with nicotine- 

 sulphate solutions. 



Material analyzed. 



Soluble nicotine after agi- 

 tating for— 



Soluble arsenic oxid (AS2O5) 

 after agitating for — 





1 hour. 



lday. 



3 days. 



lhour. 



lday. 



3 days. 



500 cubic centimeter volume tests: 



Grams. 

 0. 2748 



.2748 



.2778 

 .0000 

 .0000 



.1740 



.1750 



.1760 



.1740 



Grams. 



Grams. 

 0.2820 



.2763 



.2815 

 .0000 

 .0000 



Per cent. 

 0.00 



.45 



.44 

 .60 

 .30 



.00 



1.15 



11.04 



10.39 



.27 

 2.09 

 3.34 



Per cent. 



Per cent. 

 0.00 



Acid lead arsenate (39) plus nicotine 

 sulphate 



0.2780 



.2815 

 .0000 

 .0000 



0.34 

 .52 



.60 



Calcium arsenate (57) plus nicotine 



.50 













300 cubic centimeter volume tests: 





.00 



Calcium arsenate (32) plus nicotine 









1.09 



Calcium arsenate (59) plus nicotine 









11.50 



Calcium arsenate (464) plus nicotine 









11.86 











.27 













2.22 













3.57 















The results (Table 9) show that acid lead arsenate (sample 39) 

 when combined with nicotine sulphate gives no increase of soluble 

 arsenic and that the amount of soluble nicotine is not altered. This 

 mixture is therefore chemically compatible. 



