Select the correct answer from the list in bracket :
The cation discharged at the cathode most readily.

Answer

To solve the question, "The cation discharged at the cathode most readily," we need to analyze the given options: Fe²⁺, Cu²⁺, Pb²⁺, and H⁺.

### Step-by-Step Solution:

1. **Understand the Context of Electrolysis**: In electrolysis, cations are attracted to the cathode, where they gain electrons and are reduced. The ease with which a cation is discharged depends on its position in the reactivity series.

2. **Recall the Reactivity Series**: The reactivity series ranks metals based on their reactivity. The more reactive a metal is, the more readily it will ionize and the less readily it will be discharged at the cathode. The series generally follows:
Li > K > Na > Ca > Mg > Al > Zn > Fe > Sn > Pb > H > Cu > Ag > Au.

3. **Identify the Position of Each Cation**:
- **Fe²⁺**: Iron is above hydrogen in the series, indicating it is more reactive.
- **Cu²⁺**: Copper is below hydrogen in the series, indicating it is less reactive.
- **Pb²⁺**: Lead is also above hydrogen in the series, indicating it is more reactive.
- **H⁺**: Hydrogen is in the middle of the series.

4. **Determine the Most Readily Discharged Cation**:
- Cations that are lower in the reactivity series are discharged more readily than those that are higher up.
- Since Cu²⁺ is below H⁺, it will discharge more readily than Fe²⁺ and Pb²⁺.

5. **Conclusion**: Therefore, the cation that is discharged at the cathode most readily among the options given is **Cu²⁺**.

### Final Answer:
The correct answer is **Cu²⁺**.