The binding energy per nucleon is maximum in the case of.

Options

A. `._2^4 He`
B. `._26^56 Fe`
C. `._56^141 Ba`
D. `._92^235 U`

Explanation

To determine which element has the maximum binding energy per nucleon, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding Binding Energy per Nucleon**:
The binding energy per nucleon is a measure of the stability of a nucleus. It is defined as the total binding energy of the nucleus divided by the number of nucleons (protons and neutrons) in that nucleus.

2. **Graphical Representation**:
The binding energy per nucleon can be represented graphically against the atomic number. Generally, this graph shows that the binding energy per nucleon increases with the atomic number up to a certain point.

3. **Identifying the Peak**:
As we analyze the graph, we observe that the binding energy per nucleon increases until it reaches a peak at iron (Fe), which has an atomic number of 26. After this peak, the binding energy per nucleon starts to decrease for heavier elements.

4. **Comparing the Given Options**:
The options provided are:
- Helium (He)
- Iron (Fe)
- Beryllium (Be)
- Uranium (U)

Based on the graph, we can conclude that:
- Helium and Beryllium have lower binding energies per nucleon compared to Iron.
- Uranium, being a heavier element, has a lower binding energy per nucleon than Iron.

5. **Conclusion**:
Therefore, the element with the maximum binding energy per nucleon among the given options is Iron (Fe).

### Final Answer:
The binding energy per nucleon is maximum in the case of Iron (Fe).

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