Faraday’s law of electrolysis fails when

• A) Temperature is increased.
• B) Inert electrodes are used.
• C) A mixture of electrolytes is used.
• D) In none of these cases.

Faraday's law of electrolysis describes how the amount of substance produced at an electrode during electrolysis is proportional to the electric charge passed through the electrolyte. However, there are specific conditions under which this law may not hold true.

Factors Affecting Faraday's Law

Let's examine the options provided:

• A) Temperature is increased: While temperature can affect the rate of reaction, it does not inherently cause Faraday's law to fail.
• B) Inert electrodes are used: Inert electrodes can still allow the law to apply, as they do not participate in the reaction.
• C) A mixture of electrolytes is used: This can complicate the situation, as different ions may react differently, potentially leading to deviations from the expected results.
• D) In none of these cases: This suggests that Faraday's law remains valid under all the mentioned conditions.

Conclusion

The correct answer is C) A mixture of electrolytes is used, as this can lead to unpredictable reactions that may not align with Faraday's law.