During the electrolysis of water containing dilute sulphuric acid

Options

A. sulphate ions are oxidised at anode and hydrogen ions are reduced at cathode .
B. hydrogen ions are oxidised at cathode and hydrogen ions are reduced at anode .
C. hydrogen ions are reduced at cathode and hydroxide ions are oxidised at anode .
D. hydrogen gas is produced at anode and oxygen gas is produced at cathode .

Answer

**Step-by-Step Solution:**

1. **Understanding Electrolysis**: Electrolysis is a chemical process that uses electricity to break down compounds. In this case, we are electrolyzing water (H₂O) that contains dilute sulfuric acid (H₂SO₄) to enhance conductivity.

2. **Identifying Electrodes**: In electrolysis, two electrodes are used: the anode (positive electrode) and the cathode (negative electrode).

3. **Reactions at the Anode**: At the anode, oxidation occurs. Water molecules (H₂O) are oxidized to produce oxygen gas (O₂), hydrogen ions (H⁺), and electrons (e⁻). The reaction can be represented as:
\[ 2H_2O \rightarrow O_2 + 4H^+ + 4e^- \]
This indicates that oxygen gas is released at the anode.

4. **Reactions at the Cathode**: At the cathode, reduction occurs. Hydrogen ions (H⁺) from the water gain electrons to form hydrogen gas (H₂). The reaction can be represented as:
\[ 2H^+ + 2e^- \rightarrow H_2 \]
This indicates that hydrogen gas is produced at the cathode.

5. **Conclusion**: From the reactions, we can conclude that during the electrolysis of water containing dilute sulfuric acid, oxygen gas is produced at the anode and hydrogen gas is produced at the cathode.

6. **Evaluating Options**: Based on the reactions:
- Option A: Incorrect, sulfate ions are not oxidized.
- Option B: Incorrect, hydrogen ions are not oxidized at the cathode.
- Option C: Incorrect, hydroxide ions are not oxidized at the cathode.
- Option D: Correct, hydrogen gas is produced at the cathode and oxygen gas is produced at the anode.

**Final Answer**: The correct statement is that oxygen gas is produced at the anode and hydrogen gas is produced at the cathode.

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