658 
limited velocity, draws up a general equation for this, and derives 
from this the equation in case of rapid establishment of the equili- 
brium by assuming the velocity constant to be infinitely great. 
2. Complex Ions. 
In the following way we arrive, however, easily at the equation 
of the current potential line in a solution of complex ions. 
Let us take as an example a solution of a silver salt in ammonia, 
a 
in which the complex ions Ag(NH,), occur, which are in equili- 
+ 
brium with free ions Ag and cee NH: 
a 
Ag + 2NH, 2 Ag (NH a; 
then, as: K. Ct Cim, = CONE), 
a 
and H =e + 0.058 **log CAg 
Be o ER 10], f 5Q 10 Y EN 10 
7 —= ¢ — 0.058 log K -+ 0.058 "log C ne wht), 0.116 *°log C wii” 
When in general an z-valent ion A combines with p-molecules 
or ions 4, then 
0. 058 | 0.058 0.058 
log K+ ee “log CAB = 
n n p 
| 
| 
p ‘log Cg (10) 
By electrolysis the ions Ab, are now discharged on the cathode, 
the metal A is deposited on the cathode, 6 remaining in solution. At 
the cathode there arises, therefore, a deficit of the ions AB, and 
an excess of B. The latter moves away from the cathode through 
diffusion, the former towards the eathode. 
When a stationary state has set in, the following eqnation will 
hold for the ions AB: 
FP ei NN 
J 
This equation holds for the anodic polarisation, when the current 
density at the anode is taken positive. The index 1 refers to com- 
plex ions. 
With regard to the particles B we may state that at the cathode 
an equal number must disappear through diffusion as are liberated 
through discharge of the complex ions, hence p times the number 
of complex ions diffusing towards the cathode. 
This last quantity is 
BU i es a ein td fe Gee AN 
86400 d 
