MCQ
When an alpha particle is emitted from a radioactive source:
- AIts atomic number increases by 4
- BIts atomic number decreases by 2
- CIts atomic number increases by 2
- DIt atomic number decreases by 4
✓
Answer
- Its atomic number decreases by 2
Explanation:
When an alpha particle is emitted from a radioactive source or substance, its atomic number decreases by 2 and its atomic mass decreases by 4, which is same as that of helium ion.
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