MCQ
The number of electrons in ${[_{19}^{40}K]^{ - 1}}$ is
- A$19$
- B$40$
- C$18$
- ✓$20$
✓
Answer
Correct option: D.
$20$
d
$\left[{}_{19} K ^{40}\right]^{-1}$
$\left[{}_{19} K ^{40}\right]^{-1}$
$(-19)+(-1)=20$ electrons
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