Question

For ${}_{24}Cr$, which of the following statements is/are correct:

• A. Number of electrons with principle quantum number 3 is 13
• B. Number of electrons with azimuthal quantum number 1 is 12
• C. Number of electrons with magnetic quantum number 0 is 12
• D. Number of minimum or maximum electrons with spin quantum number $+\frac{1}{2}$ is 9 or 15

Answer 1

Answer: (A), (B), (C), (D)

The correct options are
A

Number of electrons with principle quantum number 3 is 13

B

Number of electrons with azimuthal quantum number 1 is 12

C

Number of electrons with magnetic quantum number 0 is 12

D

Number of minimum or maximum electrons with spin quantum number $+\frac{1}{2}$ is 9 or 15

Cr(24): $1s^{2}2s^{2}2p^{6}3s^{2}3p^{6}3d^{5}4s^1$
(a) Number of electrons with principle quantum number 3 is $3s^{2}3p^{6}3d^5=2+6+5=13$
(b) Number of electrons with azimuthal quantum number 1 is $2p^6,3p^6=6+6=12$
(c) Number of electrons with magnetic quantum number 0 is $3p^6$
electrons in m = 0

Total = 12 electrons
(d) Number of minimum electrons with spin quantum number $s=+\frac{1}{2}$: