Question

Match the following:

Column I		Column II
A	$s{p}^3$	i	(i) ${\left[\mathrm{Co}{\left({\mathrm{NH}}_3\right)}_6\right]}^{3+}$
B	$ds{p}^2$	ii	$[Ni(CO{)}_4]$
C	$s{p}^3{d}^2$	iii	(iii) $\left[\mathrm{Pt}{\left({\mathrm{NH}}_3\right)}_2{\mathrm{Cl}}_2\right]$
D	$d^{2}s{p}^3$	iv	$[Co{F}_6{]}^{3-}$

• A. $A-(v),B-(ii),C-(iv),D-(iii)$
• B. $A-(ii),B-(iii),C-(iv),D-(v)$
• C. $A-(ii),B-(iii),C-(i),D-(v)$
• D. $A-(ii),B-(iii),C-(iv),D-(i)$

Answer 1

Answer: (D)

I. ${\left[\mathrm{Co}{\left({\mathrm{NH}}_3\right)}_6\right]}^{3+}$

Here $\text{Co}$ is present as ${\text{Co}}^{\text{3+}}$ ion. ${\text{NH}}_{\text{3}}$ being strong field ligand pair up the unpaired electrons of $\text{Co}$ .

${}_{\text{27}}\text{Co}\text{=}\left[\text{Ar}\right]{\text{3d}}^{\text{7}}{\text{4s}}^{\text{2}}$

$\therefore {\text{Co}}^{\text{3+}}\text{=}\left[\text{Ar}\right]{\text{3d}}^{\text{6}}{\text{4s}}^{\text{0}}$



II. $\left[\text{Ni}{\left(\text{CO}\right)}_{\text{4}}\right]$

Here $\text{Ni}$ is present in its ground state. $\text{CO}$ being a strong field ligand, pair up the unpaired electrons of $\text{Ni}$

${}_{\text{28}}\text{Ni}\text{=}\left[\text{Ar}\right]{\text{3d}}^{\text{8}}{\text{4s}}^{\text{2}}$



III. $\left[\text{Pt}{\left({\left(\text{NH}\right)}_{\text{3}}\right)}_{\text{2}}{\left(\text{Cl}\right)}_{\text{2}}\right]$

Here $\text{Pt}$ is present as ${\text{Pt}}^{\text{2+}}$ ion.

${}_{\text{78}}\text{Pt}\text{=}\left[\text{Xe}\right]{\text{ 5d}}^{\text{9}}{\text{6s}}^{\text{1}}$

${\text{Pt}}^{\text{2+}}\text{=}\left[\text{Xe}\right]{\text{ 5d}}^{\text{8}}{\text{6s}}^{\text{0}}$



IV. ${\left[{\text{CoF}}_{\text{6}}\right]}^{\text{3}-}$

Here $\text{Co}$ is present as ${\text{Co}}^{\text{3+}}$ ion, $\text{F}$ being weak field ligand is unable to pair up its unpaired electrons.

${\text{Co}}^{\text{3+}}\text{=}\text{[Ar]}{\text{3d}}^{\text{6}}{\text{4s}}^{\text{0}}$