MCQ
An $\alpha$-particle captures an electron. What does it change to?
- A$He^{2+}$
- B$He$
- ✓$He^+$
- D$\alpha$
✓
Answer
Correct option: C.
$He^+$
An $\alpha $ particle has two protons and two neutrons and zero electrons. It is written as $^4_2\text{He}^{2+}$.
So if it captures an electron, the reaction is:
$^4_2\text{He}^{2+} + +e^- \rightarrow ^4_2\text{He}^{+}$
So if it captures an electron, the reaction is:
$^4_2\text{He}^{2+} + +e^- \rightarrow ^4_2\text{He}^{+}$
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