Faraday.s law of electrolysis fails when:

Options

A. Temperature is increased
B. Inert electrodes are used
C. A mixture of electrolytes is used
D. In none of the above cases

Explanation

To determine when Faraday's law of electrolysis fails, we need to analyze the conditions under which the law is applicable. Here’s a step-by-step solution:

### Step 1: Understand Faraday's Law of Electrolysis
Faraday's first law states that the amount of substance (M) deposited or liberated during electrolysis is directly proportional to the quantity of electricity (Q) passed through the electrolyte. This can be expressed mathematically as:
\[ M \propto Q \]
Where \( Q = I \cdot t \) (I is the current and t is the time).

### Step 2: Analyze the Conditions
1. **Temperature Increase**: The law does not fail with an increase in temperature. In fact, an increase in temperature can increase the conductivity of the electrolyte, allowing for more efficient electrolysis.

2. **Inert Electrodes**: The use of inert electrodes (like platinum or graphite) does not cause Faraday's law to fail. Inert electrodes do not participate in the reaction; they merely provide a surface for the electrolysis to occur.

3. **Mixture of Electrolytes**: The presence of a mixture of electrolytes can complicate the electrolysis process, but it does not inherently cause Faraday's law to fail. The law still applies, but the results may be less predictable due to the different ions present.

### Step 3: Conclusion
Given the analysis above, Faraday's law of electrolysis does not fail under any of the specified conditions (increased temperature, use of inert electrodes, or mixtures of electrolytes). Therefore, the correct answer is that Faraday's law does not fail in these cases.

### Final Answer
Faraday's law of electrolysis fails in none of the above cases.

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