Iodine in the Analysis of Alkalies and Acids. 461 



In the application of the modification of the Phelps process 

 to the indirect analysis of hydrochloric and sulphuric acids the 

 procedure was essentially the same as that detailed for the 

 analyses of barium and potassium hydroxides in Tables III and 

 IV. The acid solution to be analyzed was drawn into an 

 Erlenmeyer beaker, a measured excess of standardized alkali 

 added, and the operation completed as described. It was 

 found that barium hydroxide and potassium hydroxide may be 

 applied with equal accuracy to the analysis of both hydrochloric 

 and sulphuric acids. Some of the results obtained are given 

 in Tables V, Yl and VII. 









Tabli 



s v. 











Analyses 



?xcess of — 

 10 



N 

 of — Hydrochloric Acid 



Solution. 





(By add 



ing to ( 



Ba(OH). 2 , boiling with exces 



s of iodine 



to decoloration, 









and acidifying 



the residue.) 













Ba(OH), 











HC1 



Ba(OH) 2 



neutralized 



HOI 









taken. 



taken. 



by HU1. 



found. 



Mean. 



Variation. 





cm 3 . 



grm. 



grm. 



grm. 



grm. 



grm. 



(1) 



15 



0-17 



0:1 128 



0-0480 



0-0476 



0-0004 + 



(2) 



15 



0-17 



0-1118 



0-0475 



0-0476 



o-oooi — 



(3) 



15 



0-17 



0-1112 



0-0473 



0-0476 



0003- 



W 



25 



0*26 



0-1860 



0-0791 



0-0794 



0-0003 — 



(5) 



25 



0-26 



0-1866 



00794 



0-0794 



o-oooo± 



(6) 



35 



0-34 



0-2634 



0*1120 



0-1111 



0-0009 + 



(?) 



35 



0'34 



0-2603 

 Table 



0-1107 

 VI. 



0-1111 



0-0004 — 







Analyses 



N 

 of — Hydrochloric Acid 



Solution. 





(By add 



, IN 



ing to excess of — 



KOH, boiling 



with excess 



of iodine 



lo decoloration, 









and acidifying 



the residue ) 













KOH 











HC1 



KOH 



neutralized 



HOI 









taken. 



taken. 



by HC1. 



found. 



Mean. 



Variation. 





cm 3 . 



grm. 



grm. 



grm. 



grm. 



grm. 



(1) 



20 



0-14 



0972 



0633 



0-0633 



o-oooo ± 



(2) 



20 



0'14 



0-0975 



00634 



0633 



0001 + 



(3) 



25 



0-14 



1 2 22 



0-0795 



0-0791 



00004 + 



4) 



25 



0-14 



0-1207 



0-0785 



0-0791 



0-0006- 



An analysis of the hydrochloric acid solution by the Groger 

 method, which was found to agree in every case with the 

 gravimetric determination, gave for each 25 cm . 3 0*0801 grm. of 

 HC1, agreeing with 0*0704 grm. and 0*0791 grm. obtained by 

 the new method. An analysis of the sulphuric acid solution 

 by the Groger method gave for each 25 cm3 0*1241 grm. of 

 H 2 S0 4 agreeing with 0*1246 grm. obtained by the new method. 



