In the electrolysis of acidulated water, oxygen is produced by the discharge of..............ions at the anode.

Options

A. `OH^(-)`
B. `SO_(4)^(2-)`
C. Both (a) and (b)
D. None of these

Explanation

To answer the question: "In the electrolysis of acidulated water, oxygen is produced by the discharge of..............ions at the anode," we can follow these steps:

### Step-by-Step Solution:

1. **Understanding Electrolysis of Acidulated Water**:
- Acidulated water refers to water that has a small amount of acid (like HCl or H2SO4) dissolved in it. This helps in conducting electricity better than pure water.

2. **Identifying the Electrodes**:
- In electrolysis, there are two electrodes: the anode (positive electrode) and the cathode (negative electrode). At the anode, oxidation occurs, while at the cathode, reduction occurs.

3. **Dissociation of Water and Acid**:
- When acid is added to water, it dissociates into hydrogen ions (H⁺) and anions (like Cl⁻ from HCl or SO₄²⁻ from H₂SO₄).
- Water also dissociates into H⁺ and OH⁻ ions.

4. **Movement of Ions**:
- At the anode, negatively charged ions (anions) migrate towards it. In the case of acidulated water, the relevant anion is hydroxide (OH⁻).

5. **Oxidation Reaction at the Anode**:
- At the anode, hydroxide ions (OH⁻) are oxidized to produce oxygen gas (O₂) and water (H₂O).
- The balanced half-reaction for this process is:
\[ 4OH⁻ \rightarrow 2H₂O + O₂ + 4e⁻ \]

6. **Conclusion**:
- Therefore, the oxygen is produced by the discharge of hydroxide ions (OH⁻) at the anode during the electrolysis of acidulated water.

### Final Answer:
Oxygen is produced by the discharge of **hydroxide ions (OH⁻)** at the anode.

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