Question

Consider the ground state of Cr atom (Z = 24). The numbers of electrons with the azimuthal quantum numbers, $\mathcal{l}$ = 1 and 2 are, respectively

• A. 12 and 4
• B. 12 and 5
• C. 16 and 4
• D. 16 and 5

Answer 1

Answer: (B)

12 and 5

Answer 2

24Cr $\rightarrow$ 1s2, 2s2, 2p6, 3s2, 3p6, 3d5, 4s1

$\mathcal{l}$ = 1, $\mathcal{l}$ = 1, $\mathcal{l}$ = 2

(we know for p, l = 1 and for d, l = 2). For $\mathcal{l}$ = 1, total

number of electrons = 12

For $\mathcal{l}$ = 2, total number of electron = 5.