Structure Of Atom Question 4

Question 4 - 2024 (27 Jan Shift 1)

Consider the following complex ions

$\mathrm{P}=\left[\mathrm{FeF}_{6}\right]^{3-}$

$\mathrm{Q}=\left[\mathrm{V}\left(\mathrm{H}{2} \mathrm{O}\right){6}\right]^{2+}$

$\mathrm{R}=\left[\mathrm{Fe}\left(\mathrm{H}{2} \mathrm{O}\right){6}\right]^{2+}$

The correct order of the complex ions, according to their spin only magnetic moment values (in B.M.) is :

(1) $\mathrm{R}<\mathrm{Q}<\mathrm{P}$

(2) $\mathrm{R}<\mathrm{P}<\mathrm{Q}$

(3) $\mathrm{Q}<\mathrm{R}<\mathrm{P}$

(4) $\mathrm{Q}<\mathrm{P}<\mathrm{R}$

Show Answer

Answer (3)

Solution

$\left[\mathrm{FeF}_{6}\right]^{3-}: \mathrm{Fe}^{+3}:[\mathrm{Ar}] 3 \mathrm{~d}^{5}$

F : Weak field Ligand

1 1 1 1 1

Solutions

No. of unpaired electron’s $=5$

$\mu=\sqrt{5(5+2)}$

$\mu=\sqrt{35} \mathrm{BM}$

$\left[\mathrm{V}\left(\mathrm{H}{2} \mathrm{O}\right){6}\right]^{+2}: \mathrm{V}^{+2}: 3 \mathrm{~d}^{3}$

No. of unpaired electron’s $=3$

$\mu=\sqrt{3(3+2)}$

$\mu=\sqrt{15} \mathrm{BM}$

$\left[\mathrm{Fe}\left(\mathrm{H}{2} \mathrm{O}\right){6}\right]^{+2}: \mathrm{Fe}^{+2}: 3 \mathrm{~d}^{6}$

$\mathrm{H}_{2} \mathrm{O}$ : Weak field Ligand

1 1 1 1 1

No. of unpaired electron’s $=4$

$\mu=\sqrt{4(4+2)}$

$\mu=\sqrt{24} \mathrm{BM}$