Which of the following statement(s) is/are correct in the case of heavy water ?

Options

A. Heavy water is used as a moderator in nucler reactor
B. Heavy water is more effective as solvent than ordinary water
C. Heavy water is more associated than ordinary water
D. Heavy water has lower boiling point than oridnary water

Explanation

To determine which statements about heavy water are correct, we will analyze each statement one by one.

### Step 1: Analyze the first statement
**Statement 1:** Heavy water is used as a moderator in nuclear reactors.

**Analysis:** This statement is correct. Heavy water (D₂O) is indeed used as a moderator in nuclear reactors because it slows down neutrons without capturing them, allowing for a sustained nuclear reaction.

### Step 2: Analyze the second statement
**Statement 2:** Heavy water is more effective as a solvent than ordinary water.

**Analysis:** This statement is incorrect. Heavy water has a lower dielectric constant compared to ordinary water, which makes it less effective as a solvent. Therefore, it does not dissolve substances as efficiently as ordinary water.

### Step 3: Analyze the third statement
**Statement 3:** Heavy water is more associated than ordinary water.

**Analysis:** This statement is correct. Heavy water molecules are more associated due to stronger hydrogen bonding, resulting from the presence of deuterium (D) instead of hydrogen (H). This leads to a higher boiling point for heavy water compared to ordinary water.

### Step 4: Analyze the fourth statement
**Statement 4:** Heavy water has a lower boiling point than ordinary water.

**Analysis:** This statement is incorrect. Heavy water has a higher boiling point than ordinary water due to its higher molecular mass and stronger intermolecular forces. Therefore, it is not true that heavy water has a lower boiling point.

### Conclusion
After analyzing all the statements:
- **Correct Statements:** Statement 1 and Statement 3.
- **Incorrect Statements:** Statement 2 and Statement 4.

### Final Answer
The correct statements regarding heavy water are:
1. Heavy water is used as a moderator in nuclear reactors.
3. Heavy water is more associated than ordinary water.

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