Number of nucleons in `D_(2)` molecule is

Options

A. 1
B. 2
C. 3
D. 4

Answer

To find the number of nucleons in a \( D_2 \) molecule, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding Nucleons**:
- Nucleons are the particles found in the nucleus of an atom, which include protons and neutrons.

2. **Identifying Deuterium**:
- Deuterium (\( D \)) is an isotope of hydrogen. It has an atomic number of 1 and a mass number of 2.

3. **Determining Protons and Neutrons in Deuterium**:
- The atomic number (1) indicates that there is 1 proton in deuterium.
- The mass number (2) is the sum of protons and neutrons. Thus, the number of neutrons can be calculated as:
\[ \text{Number of Neutrons} = \text{Mass Number} - \text{Atomic Number} = 2 - 1 = 1 \]
- Therefore, each deuterium atom has 1 proton and 1 neutron.

4. **Calculating Nucleons in \( D_2 \)**:
- The \( D_2 \) molecule consists of two deuterium atoms. Thus, the total number of protons and neutrons in \( D_2 \) is:
- Protons: \( 2 \times 1 = 2 \)
- Neutrons: \( 2 \times 1 = 2 \)

5. **Total Nucleons**:
- The total number of nucleons in the \( D_2 \) molecule is the sum of protons and neutrons:
\[ \text{Total Nucleons} = \text{Number of Protons} + \text{Number of Neutrons} = 2 + 2 = 4 \]

### Final Answer:
The number of nucleons in the \( D_2 \) molecule is **4**.

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