Which of the following is an nuclear isomer of hydrogen ?

Options

A. Ortho - H
B. Para-H
C. both (1) and (2)
D. None of these

Explanation

To determine which of the following is a nuclear isomer of hydrogen, we need to understand the concept of nuclear isomers and the specific forms of hydrogen.

### Step-by-Step Solution:

1. **Understanding Nuclear Isomers**:
- Nuclear isomers are different forms of a nucleus that have the same number of protons and neutrons but differ in energy states due to the arrangement of these particles. For hydrogen, we focus on the arrangement of protons.

2. **Identifying Forms of Hydrogen**:
- Molecular hydrogen (H₂) can exist in two distinct forms based on the spins of its protons:
- **Ortho-hydrogen**: In this form, the spins of the two protons are aligned parallel to each other.
- **Para-hydrogen**: In this form, the spins of the two protons are aligned anti-parallel to each other.

3. **Determining the Nuclear Isomers**:
- Since both ortho-hydrogen and para-hydrogen consist of the same number of protons (2 protons) but differ in their nuclear spin states, they are considered nuclear isomers of hydrogen.

4. **Conclusion**:
- The nuclear isomers of hydrogen are ortho-hydrogen and para-hydrogen. Therefore, if the options provided include both ortho-hydrogen and para-hydrogen, the correct answer would be that both forms are nuclear isomers of hydrogen.

### Final Answer:
The nuclear isomers of hydrogen are ortho-hydrogen and para-hydrogen.