Gooch and Perkins — Determination of Free Iodine. 35 









Table I. 





The Action 



of Silver Reduced by Chemical Processes. 



Silver 

 taken 



Iodine 

 taken 



Increase 



in weight 

 of silver 



Error in 

 iodine Eemarks 



grm. 



grin. grm. grm. 

 (A) 

 The action of silver reduced from AgCl by zinc. 



3 



0-6473 



0-6833 



+ 0-0360 The silver 



3 



0-6473 



0-6861 



+ 0-0388 was used 



3 



0-6473 



0-6877 



+ 0-0404 without 



3 



0-6473 



0-6830 



+ 0-0357 previous 



3 



0-6473 



0-6829 



+ 0-0356 treatment 



3 



0-6461 



0-6475 



+ 0-0014 The silver was 



3 

 3 



0-6461 

 0-6461 



0-6483 

 0-6494 



+ 0-0022 previously 

 + 0-0033 treated with KI 



3 



3-27 



3 



3 



3 



0-6461 

 0-6461 



(B) 

 The action of silver reduced, from AglSTOs by zinc. 



The silver was used 



without previous 



treatment 



0-6677 

 0-6656 



+ 0-0216 

 + 0-0195 



0-6461 0-6464 +0-0003 The silver was 



0-6461 0-6472 +0*0011 previously treated 



0-6461 0-6470 +0-0009 with KI 



(C) 

 The action of silver reduced from Agl by zinc. 



0-6461 

 0-6461 

 0-6461 

 0-3217 

 0-3217 



0*6434 

 0-3217 



0-6513 

 0-6519 

 0-6514 

 0-3257 

 0-3261 



0-6444 

 0-3231 



+ 0-0052 

 + 0-0058 

 + 0-0053 

 + 0-0040 

 + 0*0044 



+ 0-0010 

 + 0-0014 



The silver 



was used 



without 



previous 



treatment 



The silver was 



previously treated 



with KI 



(D) 



The action of silver reduced from Ag 2 S by hydrogen. 

 0-6473 0-6574 +0*0101 Silver used without 



0-6473 0-6577 +0-0104 previous treatment 



3-002 0-6461 

 3 0-6461 



3 0-6461 



3 0-6461 



3 0-6461 



0-6473 

 0-6472 

 0-6475 

 0-6483 

 0-6525 



+0-0012 

 + 0-0011 

 + 0-0014 

 + 0-0022 

 + 0'0064 ; 



The 



silver was 



previously 



treated 



with KI 



(E) 



The action of silver reduced from Ag 2 by hydrogen. 



0-3217 0-3250 +0-0033 Silver used without 



previous treatment 

 * Stood for several hours in the solution. 



