ELECTROCHEMICAL INVESTIGATION OF LIQUID AMALGAMS 



THE TEMPERATURE COEFFICIENT OF THE AMALGAM CELLS. 



Since all the potentials have been measured at two or three tempera 

 tures, interest next centers in the computation of the temperature coeffi- 

 cients of the various cells. The temperature coefficient ^ over a finite 



Ay 



range of temperature is conveniently divided by the potential at o, in 

 order to compare the values obtained from the various amalgams with the 

 same range. 



The values of the quantity thus obtained, 



ATT 



for the thallium, indium, 



and tin amalgams are given in the following table as calculated from the 

 electromotive forces already recorded. The change of electromotive force 

 between o and 15 was almost always essentially identical with that 

 between 15 and 30. On account of the comparatively small change of 

 electromotive force, 15 is rather a small range for this purpose ; therefore 

 the whole range of 30 is given below as the basis for computing the 

 temperature coefficient. 



The values given in table 5 are arranged in the order of the concen- 

 tration of the most concentrated amalgam in each cell. Thus the effect of 

 concentration upon the temperature coefficient is to be ascertained at a 

 glance. 



TABLE 5. Temperature Coefficients of Electromotive Force. 



* The cells E2-E3 and F2-F3 had such small electromotive forces that the accu- 

 rate measurement of the temperature coefficients was beyond the range of the 

 apparatus. Therefore those cells were combined with cells E3-E4 and F3-F4 re- 

 spectively, for the present purpose. It should be pointed out that the error involved 

 in calculating the temperature of the indium cells is rather large, since the poten- 

 tials are small, the metal being trivalent. 



Although these results are not perfectly regular, and show evidence of 

 experimental imperfection, their general tendency is clear. 



