130 Randall — Ferric Chloride in the Zinc Reductor. 











Table II (continued). 



















Volume 















Fe 



H s S0 4 





at titra- 







Fe 







FeCl 3 . 



taken. 



3-5 #. 



HC1. 



tion. 



MnS0 4 . 



KMn0 4 . found. 



Error. 



Exp. 



cm 3 . 



grms. 



cm 3 . 



cm 3 . 



cm :; . 



grms. 



cm 3 . 



^rms. 



grms. 



8 



100 



•1748 



100 







600 



1 





30-90 



•1742 



— •0006 



9 



100 



•1748 



100 







600 



1 





30-92 



1743 



— •0005 



10* 



50 



•2532 



100 







600 



1 





44-95 



2533 



+ •0001 



11 



50 



•2532 



100 







600 



1 





45-00 



2536 



+ •0004 



12 



50 



•2532 



100 







600 



1 





45-01 



253 7 



+ •0005 



13 



50 



•2532 



100 







' 600 



1 





44-95 



2533 



+ •0001 



14 



50 



■2532 



100 







600 



1 





44-97 



2534 



+ •0002 



15 



100 



•5064 



250 







800 



1 





89-94 



5069 



+ •0005 



16 



100 



•5064 



250 







800 



1 





89-94 



5069 



+ •0005 



17* 



75 



•4872 



100 







750 



1 





70-81 



•4871 



— •0001 



18 



75 



•4S72 



100 







750 



1 





70-75 



•4867 



— •0005 



19 



75 



•4872 



100 







750 



1 





70-83 



4873 



+ '0001 



20 



■ 75 



•4872 



100 







750 



1 





70-82 



4872 



±•0000 



21 



75 



•4872 



100 







750 



1 





70-83 



4873 



+ •0001 



22 



100 



•6497 



100 







750 



1 





94-43 



6497 



±•0000 



23 



100 



•6497 



100 







750 



1 





94-44 



6498 



+ •0001 



24 



100 



•6497 



100 



10 



750 



1 





94-44 



6498 



+ •0001 



25 



100 



•6497 



100 



20 



1000 



5 





94-53 



•6503 



+ •0006 



26 



100 



•6497 



100 



25 



1000 



5 





94-53 



6503 



+ •0006 



27 



100 



•6497 



100 



25 



1000 



1 



25 



94-53 



•6503 



+ •0006 



28 



100 



•6497 



100 



25 



1000 



1 



25 



94-48 



•6500 



+ •0003 



29 



100 



•6497 



100 



25 



1000 



5 



00 



94-49 



•6501 



+ •0004 





Fe 





FeCls = 



= taken. 



H 2 S0 4 1 



cm 3 . 



grms. 



cm 3 . 



75 



•4872- 



25 



75 



•4872 



25 



75 



•4872 



25 



75 



•4872 



25 



KMn0 4 . 



Fe found. 



Error. 



cm 3 . 



grms. 



grms. 



70-75 



•4S67 



— '0005 



70-83 



•4873 



+ •0001. 



70-83 



■4873 



+ •0001 



70-88 



•4876 



+ •0004 



For purposes of comparison Table III gives some results 

 obtained by the direct evaporation of the ferric chloride solu- 

 tion with sulphuric acid. 



Table III. 

 Volume at 

 1. titration. 

 cm 3 . 



750 

 750 

 750 

 750 



These experiments show that it is possible to reduce ferric 

 chloride in the zinc reductor and to determine the iron with 

 success by potassium permanganate, provided the titration is 

 carried on in the presence of manganous sulphate and in solu- 

 tions sufficiently dilute. A small excess of hydrochloric acid 

 has no influence on the result in dilute solutions, and by dilut- 

 ing to one liter the excess may amount to as much as,25 cm3 of 

 the strongest acid. 



In closing the writer expresses his thanks to Prof. F. A. 

 Gooch for advice and assistance given during the progress of 

 the work. 



* Changed standard of solutions. 



