Be's 4^ th electron will have four quantum numbers n l m s - Vidyadip

MCQ

$Be's$ $4^{th}$ electron will have four quantum numbers

$n$ $l$ $m$ $s$

A
$1$ $0$ $0$ $+1/2$
B
$1$ $1$ $+1$ $+1/2$
✓
$2$ $0$ $0$ $-1/2$
D
$2$ $1$ $0$ $+1/2$

✓

Answer

Correct option: C.

$2$ $0$ $0$ $-1/2$

c
Electronic config for $Be$ is $1 s ^2 2 s ^2$. Fourth electron is in $s$ orbital so $n =2,l=0, m =0$ and $s =-1 / 2$

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