124 
YN, + Var, 2 Yan, . PES RGD 
When we now make the non-metal electrode MN anode, we 
withdraw the electrons. If we had to deal with a metal, hence if 
N was a metal, the electrode could maintain its potential in conse- 
quence of the fact that the withdrawn electrons are supplied in time 
by the reaction (6a), the positive ions formed going into solution. 
As N is however a non-metal, and the positive ions VN’ do not 
practically go into solution, the reaction (6a) will not take place 
to a degree of any importance. 
The only way in which the non-metal NV will be able to maintain 
its potential in the case supposed here, is this that negative ions V“ 
from the electrolyte are deposited on the electrode, and there supply 
the deficit of electrons by the splitting off of electrons. 
The processes that take place may be represented as follows: 
t 
Na nvó, Gis 
nN, 
As the heterogeneous equilibrium in the boundary layer between 
the negative ions in the electrode and in the electrolyte must set 
in with very great rapidity, it is clear that it will depend on the 
velocity of the splitting off of electrons of the negative ions whether 
the electrode maintains its potential or whether it does not. Above 
a definite current density, i.e. above a definite velocity of withdrawal 
of electrons this will no longer be the case, and a consequence of this 
will be that the electrode will contain too few electrons and too 
many negative ions. 
It follows from equation (7) for this case that the potential diffe- 
rence will become more strongly positive. 
This phenomenon of polarisation is called “supertension” in the 
case of gases, but it is not essentially different from the phenomenon 
of anodic polarisation for metals. 
It is clear that when we now proceed to the cathodic polarisation 
for non-metals this phenomenon should be ascribed to this that the 
added electrons are not quickly enough absorbed by the uncharged 
molecules or atoms, so the electron possesses a too high concentra- 
tion of electrons, and a too small concentration of negative ions. 
According to our equation (7) this gives rise to a less positive value 
of the potential difference. 
As we do not measure the potential difference, but the experi- 
