Question

Can a direct current be used for the measurement of electrical conductivity of a solution? If not, why?

Answer 1

No, direct current (DC) cannot be used for measuring the electrical conductivity of a solution because it causes several issues:

1. Electrolysis occurs, leading to the formation of gaseous products and changing the composition of the solution.
2. Corrosion and plating may happen on the electrodes due to prolonged ion transport.
3. Polarization of electrodes results from the continuous flow of DC, forming ion layers that increase resistance and cause errors in measurement.

These effects alter the actual conductivity of the solution and make the readings unreliable.

In contrast, alternating current (AC) is used because it prevents polarization and electrolysis by constantly reversing direction, avoiding continuous ion migration. This ensures more accurate and stable measurements of electrolytic conductance.