MCQ
The number of electrons in ${[_{19}^{40}K]^{ - 1}}$ is
  • A
    $19$
  • B
    $40$
  • C
    $18$
  • $20$

Answer

Correct option: D.
$20$
d
$\left[{}_{19} K ^{40}\right]^{-1}$

$(-19)+(-1)=20$ electrons

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