Question

For the measurement of conductance of an electrolytic solution,
which of the following is correct?

Direct current cannot be used as it changes the composition of solution

Alternating current cannot be used as it changes the
composition of the solution.

Both Alternating current as well as Direct current can be used as they do not change the composition of the solution

Either Alternating or Direct current can be used as both change the composition of
solution​

Answer 1

For the measurement of conductance of an electrolytic solution, the following statement is correct:

Direct current cannot be used as it changes the composition of the solution.

- When we use Direct current for the measurement of conductance of an electrolytic solution, it causes the polarization of electrodes and electrolyte.

- This leads to the change in composition and hence an error in the measurement of the conductance.

- While the Alternating Current does not cause any polarization.

- Therefore, DC is not used in measuring electrolytic conductance as it changes the composition of the solution.

Answer 2

Direct current cannot be used as it changes the composition of solution.

Option (A) is correct.

Explanation:

• An electrolytic solution consist of atoms, molecules or ions.
• This solution is conductive, therefore when electricity is passed it ionized the solution into respective ions.
• Direct current can not be used for the measurement of conductance in an electrolytic solution because it ionizes or decomposes the solution into ions, changes its composition which results in poor measurement of the conductance.