MCQ
A radioactive element ${ }_{92}^{242} X$ emits two $\alpha$-particles, one electron and two positrons. The product nucleus is represented by ${ }_{ P }^{234} Y$. The value of $P$ is $..................$
- ✓$87$
- B$88$
- C$80$
- D$86$
✓
Answer
Correct option: A.
$87$
a
$P =92-2-2+1-1-1$
$P =92-2-2+1-1-1$
$P =92-5$
$P=87$
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