Which of the following is an example of nuclear fission

Options

A. `._(1)H^(2) + ._(1)H^(2) rarr ._(2)He^(4) + gamma`
B. A + B `rarr C +` energy
C. `._(92)U^(235) + ._(0)n^(1) rarr ._(56)Ba^(141) + ._(36)Ke^(92) + 3 ._(0)n^(1) +` energy
D. `._(13)Al^(27) + ._(2)He^(4) rarr ._(15)P^(30) + ._(0)n^(1)`

Answer

To determine which of the provided options is an example of nuclear fission, we will analyze each option step by step.

### Step 1: Understand the concept of nuclear fission
Nuclear fission is a process in which a heavy nucleus splits into two or more lighter nuclei, along with the release of energy and neutrons. This is different from nuclear fusion, where two light nuclei combine to form a heavier nucleus.

### Step 2: Analyze the options
1. **Option 1**: Two particles fusing to form helium and releasing gamma radiation.
- This describes nuclear fusion, not fission. In fusion, lighter nuclei combine, which is not what we are looking for.

2. **Option 2**: A simple chemical reaction where A + B → C and energy is released.
- This is a chemical reaction and does not involve nuclear processes. Therefore, it is not an example of nuclear fission.

3. **Option 3**: The reaction where Uranium-235 absorbs a neutron and splits into Barium-141, Krypton-92, and releases 3 neutrons and energy.
- This is a classic example of nuclear fission. The Uranium nucleus is splitting into lighter nuclei (Barium and Krypton), which is characteristic of fission.

4. **Option 4**: Aluminum-27 being attacked by a helium nucleus and converting to Phosphorus-30 and a neutron.
- This describes artificial transmutation, where one element is transformed into another, but it does not involve the splitting of a nucleus, so it is not fission.

### Step 3: Conclusion
Based on the analysis, the correct answer is **Option 3**, which is an example of nuclear fission.