Heavy water is used as

Options

A. drinking water
B. detergent
C. washing water
D. a moderator

Answer

**Step-by-Step Solution:**

1. **Understanding Heavy Water**: Heavy water is chemically represented as D2O, where D stands for deuterium, an isotope of hydrogen that contains one proton and one neutron. This makes heavy water denser than regular water (H2O).

2. **Identifying the Uses of Heavy Water**: The question asks about the uses of heavy water. We need to evaluate the options provided:
- A) As drinking water
- B) As detergent
- C) As washing water
- D) As a moderator

3. **Evaluating Each Option**:
- **Option A (As drinking water)**: Heavy water is not suitable for drinking because it can be toxic in large amounts.
- **Option B (As detergent)**: Heavy water is not used as a detergent; detergents are typically made from surfactants.
- **Option C (As washing water)**: While heavy water can technically be used for washing, it is not practical or common.
- **Option D (As a moderator)**: Heavy water is widely used as a neutron moderator in nuclear reactors. It slows down neutrons, allowing for more effective nuclear reactions.

4. **Conclusion**: After evaluating all options, the correct answer is D) as a moderator. Heavy water (D2O) is essential in controlling nuclear reactions by moderating the speed of neutrons.

**Final Answer**: Heavy water is used as a moderator in nuclear reactors.

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