[ 377 ] 



XLIL On the Determination of Chemical Affinity in terms of 

 Electromotive Force. — Part VIII. By C. R. Alder Wright, 

 D.Sc. (Lond.), F.R.S., Lecturer on Chemistry and Physics, 

 and C. Thompson, Demonstrator of Chemistry, in St. Mary's 

 Hospital Medical School. 



[Concluded from p. 301.] 



156. fj^OR the sake of comparison with the amounts of heat 

 -A- developed on intermixture of strong and weak 

 solutions, the following series of observations were made with 

 solutions of zinc and cadmium chlorides, these salts being 

 more especially selected because the calorimetric observations 

 detailed later on (§ 160) showed that, whereas the heat of 

 dilution of cadmium-sulphate solutions is greater than that of 

 zinc-sulphate solutions, the opposite relationship holds with 

 the solutions of the chlorides of these metals. 



Cadmium Chloride. — Observations with diffusion-cells. 

 Electro-cadmium plates : probable error of each value not ex- 

 ceeding + *5 millivolt. 









Value of n. 





















8-0. 



4-45. 



31. 21. 



•67. 



•25. 



Ill 



161 



23-8 



26-4 



331 



43-3 



54-4 



8-0 





77 



10-3 



17-0 



272 



3S-3 



4'45 







2-6 



9-3 



19-5 



30-6 



3-1 









67 



169 



280 



21 











10-2 



21-3 



•67 













11-1 



Zinc Chloride.- 

 mated-zinc plates 



Observations with diffusion-cells. Amalga- 

 probable error less than ±1*0 millivolt. 











Value of 



»• 







Value of m. 

















9-8. 



64. 



33. 



204. 



•754. 



•25. 



•172. 



21-4 



112-0 



186-3 



207-1 



2181 



239-7 



254-1 



2590 



9-S 





743 



951 



106-1 



1277 



1421 



1470 



61 







20-8 



31-8 



53-4 



67-8 



72-7 



33 









110 



32-6 



47-0 



51-9 



2-04 











21-6 



360 



40-9 



•7:>4 













14-4 



19-3 



•25 















49 



reducing 



these two sets of figures to the values for 

 n } and plotting the resulting numbers, the 



On 

 ??*~10 as 



curves marked 1 and 2 respectively (Pl.VX fig. 5) are obtained 

 evidentlv the value of b in the expression E = e-\-a — b greatly 



Phil. 1 Mag. S. 5. Vol. 17. No. 107. May 1884. 2 C 



