The curve of blinding energy per nucleon as a function of atomic mass number has a sharp peak for helium nucleus. This implies that helium.

Options

A. Is very stable
B. Is radioactive
C. Can easily be broken up
D. Can be used as fissionable material

Answer

To solve the question regarding the binding energy per nucleon for the helium nucleus, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding Binding Energy per Nucleon**:
- Binding energy per nucleon is defined as the energy required to remove a nucleon from a nucleus. It is an important measure of the stability of a nucleus.

2. **Analyzing the Curve**:
- The question states that there is a sharp peak in the curve of binding energy per nucleon as a function of atomic mass number (A). This indicates that at this point, the binding energy per nucleon is at its maximum.

3. **Implications of a Sharp Peak**:
- A sharp peak in the binding energy per nucleon implies that the nucleus at this point (in this case, helium) is particularly stable. This means that the forces holding the nucleons together are very strong.

4. **Stability of Helium**:
- Since helium has a high binding energy per nucleon, it suggests that helium nuclei are more stable compared to other nuclei with lower binding energy per nucleon. This stability means that helium is less likely to undergo radioactive decay.

5. **Conclusion**:
- Therefore, the sharp peak in the binding energy per nucleon curve for helium indicates that helium is a very stable nucleus.

### Final Answer:
The sharp peak for helium in the binding energy per nucleon curve implies that helium is a very stable nucleus.

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