Gooch and Ward — Copper Oxalate in Analysis. 453 



Copper 



taken 



grm. 



Volume 



of the 



liquid 



cm 3 . 



Table III. 

 The Effect of Active Acids. 



Oxalic 

 acid 

 used 

 grm. 



Volume of 

 sulphuric 

 acid or of 

 nitric acid 

 cm 3 . 



Copper 

 found 



Error 

 grm. 



Average 

 error 

 grm. 



0-0502 

 0-0502 

 0-0502 

 0-0502 

 0-0502 



0-0515 

 0-0530 

 0-0502 

 0-0502 

 0-0502 

 0-0502 

 0-1500 

 0-2377 

 0-2530 

 0-2897 



0-1333 

 0-1366 

 0-1443 

 0-2388 

 0-0502 



0-0504 

 0-0504 



Volume at precipitation approximates 1 00 cm 

 H 2 SQ 4 

 0-1 



100 

 100 

 100 

 100 

 100 



100 

 100 

 100 

 100 

 100 

 100 

 100 

 100 

 100 

 100 



50 



50 

 50 

 50 

 50 



50 

 50 



4-0 

 4-0 

 4-0 

 4-0 

 4-0 



4-0 

 4-0 

 4-0 

 4-0 

 5-0 

 5-0 

 2-0 

 4-0 

 4-0 

 4-0 



0-5 

 1-0 

 2-0 

 2-0 



HNOc 



O'l 



o-i 

 o-i 

 o-i 



5-0 

 5-0 



o-i 



0-1 



o-i 

 o-i 



0-0454 

 0-0481 

 0-0484 

 0-0474 



0-0481 



0-0499 

 0-0505 

 0-0471 

 0-0472 

 0471 

 0*0468 

 0-1476 

 0-2356 

 0-2497 

 0-2880 



0-0048 ) 

 0-0021 | 

 0-0018 y 

 0-0028 | 

 0*0021 J 



0-0016 

 0-0025 

 •0-0031 

 0-0030 

 0-0031 

 0-0034 

 0-0024 

 ■0-0021 

 •0-0033 _ 

 0-0067 j 



B 



Volume at precipitation 50 cm 3 . 



4-0 

 2-0 

 2-0 

 2-0 



2-0 



4-0 

 4-0 



0-1 



0-1 



o-i 



111 



4-0 



25-0 

 40-0 



0-1327 

 0-1360 

 0-1434 

 0-2384 

 0-0494 



0-0491 



0-0487 



0-0024 



y —0-0031 



— 0-0006"] 



— 0-0006 | 



—0-0009 y 



— 0*0004 I 



— 0-0008 J 



— 0-0013 ) 



— 0-0017 [ 



miscible liquid less capable of dissolving the precipitated 

 oxalate. The experiments of Table IV were made to test the 

 effect of alcohol as suggested by Gibbs.* The results given in 

 A show the effects of alcohol without nitric acid ; those of B 

 show the effect of alcohol with nitric acid. 



It is plain that the presence of alcohol improves the results 



of the process as compared with the results obtained at similar 



dilutions of the oxalic acid solution, either with or without 



nitric acid ; and, if the effect of nitric acid in the aqueous 



* This Journal, xliv, 214, 1867. 



Am. Jour. Sci.— Fourth Series, Vol. XXVII, No. 162. 

 31 



-June, 1909. 



