What is the product formed at the cathode in the electrolysis of aqueous CuSO4?

Options

A. Copper metal
B. Oxygen gas
C. Hydrogen gas
D. Sulphur

Explanation

To determine the product formed at the cathode during the electrolysis of aqueous CuSO4, we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Electrolyte**: The electrolyte in this case is aqueous CuSO4 (copper(II) sulfate). When dissolved in water, it dissociates into copper ions (Cu²⁺) and sulfate ions (SO₄²⁻).

2. **Set Up the Electrolysis Apparatus**: In an electrolytic cell, there are two electrodes: an anode (positive) and a cathode (negative). The anode is connected to the positive terminal of the battery, and the cathode is connected to the negative terminal.

3. **Determine Ion Migration**: Since the cathode is negatively charged, cations (positively charged ions) will migrate towards it. In the case of CuSO4, the cation is Cu²⁺. Additionally, H⁺ ions from the water (due to its dissociation) can also migrate towards the cathode.

4. **Consider the Reduction Process**: At the cathode, reduction occurs. This means that the ions gaining electrons will be reduced to their elemental form. The relevant reactions at the cathode can be:
- Cu²⁺ + 2e⁻ → Cu (s) (copper metal)
- 2H⁺ + 2e⁻ → H₂ (g) (hydrogen gas)

5. **Refer to the Electrochemical Series**: To determine which ion will be reduced preferentially, we can refer to the electrochemical series. Copper ions (Cu²⁺) have a higher reduction potential compared to hydrogen ions (H⁺), meaning Cu²⁺ will be reduced first.

6. **Conclusion**: Therefore, during the electrolysis of aqueous CuSO4, the product formed at the cathode is copper metal (Cu).

### Final Answer:
The product formed at the cathode during the electrolysis of aqueous CuSO4 is **copper metal (Cu)**.

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