What is heavy water ?

Options

A. `H_(2)O^(18)`
B. `D_(2)O`
C. `H_(2)O^(17)`
D. `H_(2)O`

Explanation

**Step-by-Step Solution:**

1. **Definition of Heavy Water:**
Heavy water is a form of water that contains a higher proportion of the isotope deuterium (D) instead of the common hydrogen isotope (H).

2. **Chemical Formula:**
The chemical formula for heavy water is D₂O. In this formula, "D" represents deuterium, which is an isotope of hydrogen.

3. **Isotopes of Hydrogen:**
Hydrogen has three isotopes:
- Protium (¹H) with an atomic mass of 1.
- Deuterium (²H or D) with an atomic mass of 2.
- Tritium (³H or T) with an atomic mass of 3.

4. **Comparison with Regular Water:**
Regular water is represented by the formula H₂O, where H is the common hydrogen isotope. In heavy water, the hydrogen atoms are replaced by deuterium atoms.

5. **Properties of Heavy Water:**
Heavy water has different physical and chemical properties compared to regular water due to the presence of deuterium. It is denser than regular water and has a higher boiling point.

6. **Applications of Heavy Water:**
Heavy water is used in nuclear reactors as a neutron moderator and in various scientific research applications.

**Final Answer:**
Heavy water is D₂O, where D is the isotope deuterium, and it differs from regular water (H₂O) by having deuterium instead of hydrogen.

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