Fission of nuclei is possible because the binding energy per nuclei in them

Options

A. increases with mass number at high mass numbers
B. decreases with mass number at high mass number
C. increases with mass number ata low mass number
D. decreasewith mass number at low mass number

Explanation

To solve the question regarding the fission of nuclei and the binding energy per nucleon, we can break it down into several steps:

### Step 1: Understand Binding Energy per Nucleon
The binding energy per nucleon is the energy required to remove a nucleon (proton or neutron) from a nucleus. It is a measure of the stability of a nucleus. Higher binding energy per nucleon indicates a more stable nucleus.

### Step 2: Analyze the Graph of Binding Energy
In the context of nuclear physics, the graph of binding energy per nucleon versus mass number (A) shows how binding energy changes as the size of the nucleus increases. For lighter nuclei, the binding energy per nucleon tends to increase, reaching a peak around iron (Fe), and then decreases for heavier nuclei.

### Step 3: Identify the Process of Fission
Fission is the process where a heavy nucleus splits into two lighter nuclei, releasing energy. This process is favorable when the binding energy per nucleon of the resulting lighter nuclei is greater than that of the original heavy nucleus.

### Step 4: Relate Binding Energy to Fission
For heavy nuclei, the binding energy per nucleon decreases as mass number increases. This means that heavy nuclei are less stable and can undergo fission more easily. When they split, the resulting lighter nuclei have a higher binding energy per nucleon, which releases energy.

### Step 5: Conclusion
Thus, the fission of nuclei is possible because the binding energy per nucleon decreases with increasing mass number for heavy nuclei. This decrease indicates that heavy nuclei are less stable and can release energy when they undergo fission.

### Final Answer
Fission of nuclei is possible because the binding energy per nucleon decreases with increasing mass number in heavy nuclei.

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