^{12}This is apparent from a mathematical perspective by examination of the Nernst equation: if the concentrations are
equal (i.e. C_{1} = C_{2}), then the ratio of C_{1}
C_{2} will be equal to 1. Since the logarithm of 1 is zero, this predicts zero voltage
generated across the membrane. From a chemical perspective, this corresponds to the condition where random ion migration
through the porous membrane is equal in both directions. In this condition, the Nernst potentials generated by the
randomly-migrating ions are equal in magnitude and opposite in direction (polarity), and therefore the membrane generates
zero overall voltage.