Question

The correct set of four quantum numbers for valence electrons of rubidium atom (Z=37) is
A. 5,0,0,`+1/2`
B. `5,1,0,+1/2`
C. `5,1,1,+1/2`
D. `6,0,0,+1/2`

Answer 1

Correct Answer - A
Electronic configuration of `Rb_((37))` is `1s^2 2s^2 2p^6 3s^2 3p^6 3d^10 4s^2 4p^6 5s^1`
So for the valence shall electron `(5s^1)`
n=5, l=0, m=0, `s=+1/2`