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Nuclei — Physics STD 12 Science — Question

Gujarat BoardEnglish MediumSTD 12 SciencePhysicsNuclei1 Mark
MCQ
An $\alpha$-particle captures an electron. What does it change to?
  • A
    He2+
  • B
    He
  • C
    He+
  • D
    $\alpha$
✓

Answer

  1. He+

Explanation:

An α 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− → $^4_2\text{​He}^{+}$

 

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