A conductance cell of which the electrodes are provided with a 110 nm
thick Ta2O5 insulating film is proposed and realized. The stable and v
ery low impedance of the total oxide/solution interface largely reduce
s interference from redox processes. Measurement results, given as an
output voltage between 10 and 600 mV as a function of the specific res
istance between 0.1 and 8 kOMEGA, are shown to be in agreement with th
eoretically calculated results, both at the constant current and const
ant voltage mode of operation.