With platinum electrodes, hydrogen is liberated at the ………… and oxygen at the …………….. During the electrolysis acidified water.

Options

A. cathode, anode
B. anode, cathode
C. anode, anode
D. cathode, cathode

Explanation

**Step-by-Step Solution:**

1. **Understanding Electrolysis of Acidified Water**:
- Electrolysis is a process that uses electricity to break down a compound into its elements. In this case, we are looking at acidified water, which is water mixed with an acid (like sulfuric acid) to improve its conductivity.

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

3. **Movement of Ions**:
- When an electric current is passed through acidified water, the water dissociates into hydrogen ions (H⁺) and hydroxide ions (OH⁻).
- The H⁺ ions are attracted to the cathode (negative electrode), while the OH⁻ ions are attracted to the anode (positive electrode).

4. **Reactions at the Electrodes**:
- At the **anode**, oxidation occurs. The OH⁻ ions lose electrons and are oxidized to form oxygen gas (O₂).
- The balanced reaction at the anode can be represented as:
\[ 4OH⁻ \rightarrow 2H₂O + O₂ + 4e⁻ \]
- At the **cathode**, reduction occurs. The H⁺ ions gain electrons and are reduced to form hydrogen gas (H₂).
- The balanced reaction at the cathode can be represented as:
\[ 2H⁺ + 2e⁻ \rightarrow H₂ \]

5. **Conclusion**:
- Therefore, during the electrolysis of acidified water with platinum electrodes, hydrogen is liberated at the **cathode** and oxygen at the **anode**.

**Final Answer**:
- Hydrogen is liberated at the **cathode** and oxygen at the **anode**.

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