When helium nuclei bombard beryllium nuclei ,then

Options

A. Electrons are emitted
B. Protons are emitted
C. Neutrons are emitted
D. protons and neutrons are emitted

Answer

To solve the problem of what happens when helium nuclei bombard beryllium nuclei, we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Nuclei Involved**:
- Helium nuclei (α-particles) have an atomic number (Z) of 2 and a mass number (A) of 4.
- Beryllium nuclei have an atomic number (Z) of 4 and a mass number (A) of 9.

2. **Write the Reaction**:
- When helium nuclei bombard beryllium nuclei, the reaction can be represented as:
\[ \text{He} + \text{Be} \rightarrow \text{C} + \text{n} \]
- Here, we are looking to produce carbon (C) and a neutron (n).

3. **Conservation of Charge**:
- The total charge before the reaction:
- Helium: Z = 2
- Beryllium: Z = 4
- Total charge = 2 + 4 = 6
- After the reaction, carbon has an atomic number of 6, which maintains the conservation of charge.

4. **Conservation of Mass Number**:
- The total mass number before the reaction:
- Helium: A = 4
- Beryllium: A = 9
- Total mass number = 4 + 9 = 13
- After the reaction, carbon has a mass number of 12, and since one neutron is emitted (mass number = 1), the total mass number is:
- Carbon: A = 12 + Neutron: A = 1 = 13
- This also maintains the conservation of mass number.

5. **Conclusion**:
- The reaction results in the formation of carbon and the emission of a neutron. Thus, the correct answer is that neutrons are emitted.

### Final Answer:
When helium nuclei bombard beryllium nuclei, neutrons are emitted, resulting in the formation of carbon.

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