How is an a-particle different from a helium atom?

Explanation

To understand how an alpha particle is different from a helium atom, we need to analyze their structures in terms of protons, neutrons, and electrons.

### Step-by-Step Solution:

1. **Identify the Structure of a Helium Atom:**
- A helium atom is represented as \( \text{He}_{2}^{4} \).
- It has an atomic number of 2, which means it has 2 protons.
- Since it is a neutral atom, it also has 2 electrons.
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