48 Brown — Wo?*Jc on the Interaction of Hydrochloric Acid. 



ganate run in to color as before. The results showed all desired 

 agreement with those of Table II, proving that the removal of 

 chlorine during the hour's digestion has no effect on the 

 oxidizing material other than chlorine retained. As these 

 experiments were merely confirmatory, they are not given here. 

 Wagner has also shown the diminishing effect of manganous 

 chloride* and sulphate in the amount of permanganate appar- 

 ently reduced by hydrochloric acid after the above method of 

 experimentation. This part of his work has also been investi- 

 gated and gives results as shown in Table III, in which the 

 chlorine was not removed during digestion, and Table IV, in 

 which the chlorine was thus removed. Difficulty was encoun- 

 tered in maintaining the solutions of manganous salts at con- 

 stant value in neutral solution, basic manganese salts settling 

 out on standing a few days. One hundred and twenty cubic 

 centimeters of normal hydrochloric acid to the liter were 

 therefore added in making up the tenth-normal manganous 

 salts. This would make an excess of approximately l - 20 cm3 of 

 normal hydrochloric acid in 9*90 cm3 of the solutions, the amount 

 used in the experiments ; allowauce was made for this excess, 

 and only 98*80 cm3 of normal hydrochloric acid used. 



[20 cm3 ^(H 4 N) 2 C 2 4 = 40-99' 

 grm. per cm 3 . 



Table III. 

 m3 KMn0 4 Oxygen value KMn0 4 = 0-0003903 

 9-90 cm3 H 2 C 2 O 4 =20-75 cmS KMn0 4 -l 



N 

 ^HCl 



N 



ro HC1 



KMn0 4 



before 



digestion 



b 



-4-3 



e6 



TT .3 



H 2 C 2 4 



KMn0 4 

 to color 



KMn0 4 

 appar- 

 ently re- 

 duced 



KMn0 4 

 appar- 

 ently un- 

 reduced 



cm 3 . 



cm 3 . 



cm 3 . 



ft 



S 



<4H B 



o 



cm 3 . 



cm 3 . 



during 



digestion 



cm 3 . 



during 



digestion 



cm 3 



100 



9 90 



9-90 



50 



60 



9-90 



13-08 



2-23 



7-67 



100 



9-90 



9-90 



50 



60 



9-90 



13-18 



2-33 



7-57 



100 



9-90 



9-90 



50 



60 



9-90 



13-33 



2-48 



7-42 



100 



990 



9'90 



50 



60 



9-90 



13-17 



2-32 



7-58 



100 



9-90 



9-90 



50 



60 



9-90 



13-22 



237 



7-53 





N 

 ^MnCl 2 



















em 3 

















100 



9-90 



9-90 



50 



60 



9-90 



12-45 



1-60 



8-30 



100 



9-90 



9-90 



50 



60 



9-90 



12-38 



1-53 



8-37 



100 



9-90 



9-90 



50 



60 



9-90 



12-59 



1-74 



8-16 



100 



9-90 



9-90 



50 



60 



9-90 



1235 



1-50 



8-40 



100 



9-90 



D-9() 



50 



60 



9-90 



12-36 



1-51 



8-39 



Loc. cit., p. 



