MCQ
An atom has $2$ electrons in $K$ shell, $8$ electrons in $L$ shell and $6 $ electrons in $M$ shell. The number of $s$-electrons present in that element is
- ✓$6$
- B$5$
- C$7$
- D$10$
✓
Answer
Correct option: A.
$6$
a
(a) Shell $= K, L, M = $ $1{s^2}$ $2{s^2}2{p^6}$ $3{s^2}3{p^4}$
(a) Shell $= K, L, M = $ $1{s^2}$ $2{s^2}2{p^6}$ $3{s^2}3{p^4}$
Hence the number of $s $ electron is $ 6$ in that element.
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