3^2 Table 383. 



COMPOSITION AND ELECTROMOTIVE FORCE OF VOLTAIC CELLS. 



The electromotive forces given in this table approximately represent what may be expected from a cell in good work 

 ing order, but with the exception of the standard cells all of them are subject to considerable variation. 



Name of 



cell. 



Bunsen . 



Chromate 



Daniell* 



Grove . 



(a) Double Fluid Cells. 



Negative pole. 



Amalgamated zinc 



Solution. 



S I part H2SO4 to ) 

 ) 12 parts H.2O . ) 



■ i2partsK2Cr207"| 

 to 25 parts of I 

 H2SO4 and 100 I 

 parts H2O . . J 



( I part H2SO4 to I 

 I 12 parts H2O . i 



( I part H2SO4 to ) 

 I 4 parts H2O . i 



( I part H2SO4 to ( 

 I 12 parts H2O . i 



J 5% solution of ) 

 \ ZnS04 + 6H2O i 



( I part NaCl to j 

 \ 4 parts H2O . i' 



{ I part H2SO4 to 

 ( 12 parts H2O . 



Solution of ZnS04 



( H2SO4 solution, ( 

 j density 1.136 . ) 



( H2SO4 solution, 

 ( density 1.136 . 



( H2SO4 solution, 

 I density 1.06 . 



J H2SO4 solution, 

 \ density 1.14 . 



( H2SO4 solution, ) 

 j density 1.06 . ) 



NaCl solution . . 



^ I part H2SO4 to ( 

 } 12 parts H2O ) 



Solution of MgS04 



Positive 

 pole. 



Carbon 



Solution. 



Copper 



Platinum 



Fuming HNOa 

 HNO3, density 1.38 



I part H2SO4 to ) 

 12 parts H2O . ) 



12 parts K2Cr207 ( 

 to 100 parts H2O J 



Saturated solution ) 

 ofCuS04+sH20S 



Carbon 



Fuming HNO3 . . 

 HNO3, density 1.33 

 Concentrated HNOs 



HNO3, density 1.33 



HNO3, density 1.19 



" density 1.33 



C Paste of protosul- ) 

 < phate of mercury > 

 ( and water . . . ) 



Solution of K2Cr207 



1.94 

 1.86 



2.00 



2.03 

 1.06 

 1.09 

 1.08 

 1.05 



1-93 

 1.66 



1-93 



1.79 



1.71 



1.66 



1. 61 

 1.88 



1.50 



2.06 



* The Minotto or Sawdust, the Meidinger, the Callaud, and the Lockwood cells are raodificatioas of the 

 and hence have about the same electromotive force. 



Smithsonian Tables. 



■J 



Daniell, 



