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
$P =92-2-2+1-1-1$

$P =92-5$

$P=87$

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