Question

Which one of the following has a magnetic moment of $1.75B.M.$ ?

• A. $T{i}^{3+}$
• B. $V^{3+}$
• C. $C{r}^{3+}$
• D. $F{e}^{3+}$

Answer 1

Answer: (A)

Magnetic moment, $\mu =\sqrt{n(n+2)}BM$

where $n=$ number of unpaired electrons.

Ion	Outermost electronic configuration	No. of unpaired $e^{-}$	Magnetic moment (BM)
$V^{3+}$		2	$\sqrt{2(2+2)}=2.82$
$C{r}^{3+}$		3	$\sqrt{3(3+2)}=3.87$
$F{e}^{3+}$		5	$\sqrt{5(5+2)}=5.91$
$T{i}^{3+}$		1	$\sqrt{1(1+2)}=1.73$

Thus, it is $T{i}^{3+}$ ion, magnetic moment which is $1.75BM$