`D_(2)O` is used more in

Options

A. Chemical industry
B. Nuclear moderater
C. Pharmaceutical preparation
D. Insecticide preparations

Answer

To solve the question about the uses of D₂O (deuterium oxide or heavy water), we can follow these steps:

### Step-by-Step Solution:

1. **Identify D₂O**:
- D₂O is known as deuterium oxide, commonly referred to as heavy water. It is similar to regular water (H₂O) but contains deuterium (D), which is an isotope of hydrogen.

2. **Understand Deuterium**:
- Deuterium (D) has an atomic number of 1 and a mass number of 2, consisting of one proton and one neutron. This distinguishes it from regular hydrogen (H), which has one proton and no neutrons.

3. **Applications of D₂O**:
- D₂O has several applications, but the most significant one is in the nuclear industry. It is primarily used as a moderator in nuclear reactors.

4. **Role of D₂O as a Moderator**:
- In nuclear reactors, D₂O slows down fast-moving neutrons, making them more likely to induce fission when they collide with fissile material (like uranium-235). This is crucial for maintaining a controlled nuclear reaction.

5. **Evaluate Other Options**:
- While D₂O can have other uses in pharmaceutical preparations and possibly in some insecticides, its primary and most notable application is in the nuclear industry as a moderator.

6. **Conclusion**:
- Based on the analysis, the correct answer to the question is that D₂O is used more in the nuclear industry as a moderator.

### Final Answer:
D₂O is used more in the nuclear industry as a moderator.

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