Question

The calculated magnetic moment of a divalent ion of an atom with atomic number $24$ in aqueous solution is

• A. $4.90BM$
• B. $5.92BM$
• C. $3.87BM$
• D. $2.84BM$
• E. $1.73BM$

Answer 1

The correct option is A $4.90BM$

${}_{24}M=1s^2,2s^2,2p^6,3s^2,3p^6,3d^5,4s^1$
$=\left[Ar\right]3d^{5}4s^1$
$M^{2+}=\left[Ar\right]3d^4$
$\therefore$ Number of unpaired electrons $=4$
$\therefore$ Mognetic moment; $\mu =\sqrt{n(n+2)}$
$\therefore \mu =\sqrt{4(4+2)}$
$=\sqrt{24}=4.90BM$.