Heavy water freezes at

Options

A. `0^@C`
B. `3.8^@C`
C. `38^@C`
D. `-0.38^@C`

Answer

To solve the question regarding the freezing point of heavy water (D2O), we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Composition of Heavy Water:**
- Heavy water is chemically represented as D2O, where D stands for deuterium, an isotope of hydrogen that contains one neutron and one proton in its nucleus, unlike regular hydrogen (H) which has only one proton.

2. **Compare with Regular Water:**
- Regular water (H2O) consists of two hydrogen atoms (H) and one oxygen atom (O). The freezing point of regular water is known to be 0°C.

3. **Identify the Freezing Point of Heavy Water:**
- The question asks for the freezing point of heavy water. It is known from scientific data that heavy water freezes at a higher temperature than regular water.

4. **Recall the Freezing Point of Heavy Water:**
- The freezing point of heavy water (D2O) is approximately 3.8°C.

5. **Select the Correct Option:**
- Among the given options:
- 0°C
- 3.8°C
- 38°C
- -0.38°C
- The correct answer is 3.8°C.

### Final Answer:
Heavy water freezes at **3.8°C**.

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