238 Gooeh and Edgar — Reduction of Yanadic Acid. 



Ferric alum 

 10 % sol. 



Phosphoric 

 acid 

 syrup 



Table III. 



KMn0 4 VoO., 

 N H ._- taken as 

 10 x 1 '°° 3 NaV0 3 



v 2 o 6 



calculated 



from 

 oxidation 

 from V 2 2 



Error 

 in terms 

 of V a 6 



cm 3 



cm 3 



cm 3 



grin. 



grm. 



grm. 



25 



5 



43-10 



0-1381 



0-1378 



— 0-0003 



25 



5 



43-20 



0-1381 



0-1 381 



o-oooo 



25 



5 



43-30 



0-1381 



0-1384 



+ 0-0003 



25 



5 



43-28 



01381 



0-1384 



+ 0-0003 



25 



5 



43-32 



0-1381 



0-1385 



+ 0-0004 



15 



3 



21-60 



0-0691 



0-0690 



—o-oooi 



15 



3 



21-62 



00691 



0-0691 



o-oooo 



15 



3 



21-80 



0-0691 



0-0696 



+ 0-0005 



40 



8 



64-90 



0-2072 



0-2075 



+ 0-0003 



Finally, it is evident that the assumptions upon which Glas- 

 mann's method for the determination of vanadic and molybdic 

 acids is based — viz., that the condition of vanadium in a. solu- 

 tion reduced by magnesium is definitely that of V 2 3 and that 

 the condition of vanadium in a solution reduced by zinc and 

 exposed subsequently to the air is definitely that of V a O a — are 

 unwarranted. 



