Question

The total spin and magnetic moment for the atom with atomic number $7$ are:

• A. $\pm 3,\sqrt{3}BM$
• B. $\pm 1,\sqrt{8}BM$
• C. $\pm \frac{3}{2}\sqrt{15}BM$
• D. $0,\sqrt{8}BM$

Answer 1

Answer: (C)

Atomic number $=7$
Structure is $1s^2,2s^2,2p^3$

$n=3$,
Total spin $=\pm \frac{1}{2}n=\pm \frac{1}{2}\times 3=\pm \frac{3}{2}$
Magnetic moment $=\sqrt{n(n+2)}$ $=\sqrt{3(3+2)}=\sqrt{15}BM$