Which of the following reaction does not take place at cathode

Options

A. `Ag^(+)+e^(-)toAg`
B. `Cl^(-)toCl+e^(-)`
C. `H^(+)+e^(-)toH`
D. `Cu^(2+)+2e^(-)toCu`

Answer

To determine which reaction does not take place at the cathode, we first need to understand the fundamental concepts of electrochemistry, particularly the roles of the anode and cathode in an electrochemical cell.

### Step-by-Step Solution:

1. **Understand the Role of the Cathode**:
- The cathode is the electrode where reduction occurs. This means that at the cathode, species gain electrons.

2. **Identify the Nature of Reactions**:
- Since reduction occurs at the cathode, we need to identify the reactions provided in the options and determine whether they involve reduction (gain of electrons) or oxidation (loss of electrons).

3. **Analyze Each Reaction**:
- Go through each of the given reactions (not provided in the question, but typically you would have a list) and classify them based on whether they represent reduction or oxidation.
- If a reaction involves the loss of electrons, it is an oxidation reaction and does not occur at the cathode.

4. **Select the Correct Answer**:
- After analyzing all the reactions, the one that involves oxidation (loss of electrons) is the reaction that does not take place at the cathode.

5. **Conclusion**:
- Based on the analysis, you would select the option that corresponds to the oxidation reaction as the answer to the question.