Question

Which of the following statements is correct for $[Mn(CN{)}_6{]}^{3-}$ according to valence bond theory?

• A. $d^{2}s{p}^3$, inner orbital complex, paramagnetic, $2.87B.M$
• B. $d^{2}s{p}^3$, inner orbital complex, diamagnetic, zero magnetic moment
• C. $d^{2}s{p}^3$, outer orbital complex, paramagnetic, $3.87B.M$
• D. $ds{p}^2$, outer orbital complex, diamagnetic, zero magnetic moment

Answer 1

Answer: (A)

In $[Mn(CN{)}_6{]}^{3-}$, oxidation state of $Mn=+3,M{n}^{3+}=3d^4$
$[Mn(CN{)}_6{]}^{3-}$ :
It has two unpaired electrons.
$\mu =\sqrt{n\left(n+2\right)}=\sqrt{2\left(2+2\right)}=\sqrt{8}$
$=2.87B.M.$