Which of the following complexes show linkage isomerism?
Arrange the following complexes in the increasing order of conductivity of their solution
$$\left[\mathrm{Co}\left(\mathrm{NH}_3\right)_3 \mathrm{Cl}_3\right],\left[\mathrm{Co}\left(\mathrm{NH}_3\right)_4 \mathrm{Cl}_2\right] \mathrm{Cl},\left[\mathrm{Co}\left(\mathrm{NH}_3\right)_6\right] \mathrm{Cl}_3,\left[\mathrm{Cr}\left(\mathrm{NH}_3\right)_5 \mathrm{Cl}\right] \mathrm{Cl}_2$$
Ions or molecules present outside the coordination sphere are ionisable. A complex which gives more ions on dissolution, is more conducting.
$$\underset{(1 \text { ion) }}{\left[\mathrm{Co}\left(\mathrm{NH}_3\right)_3 \mathrm{Cl}_3\right]}<\underset{\text { (2 ions) }}{\left[\mathrm{Co}\left(\mathrm{NH}_3\right)_4 \mathrm{Cl}_2\right] \mathrm{Cl}}<\underset{\text { (3 ions) }}{\left[\mathrm{Cr}\left(\mathrm{NH}_3\right)_5 \mathrm{Cl}\right] \mathrm{Cl}_2}<\underset{\text { (4 ions) }}{\left[\mathrm{Co}\left(\mathrm{NH}_3\right)_6\right] \mathrm{Cl}_3}$$
Here, number of ions increases and conductivity increases.
A coordination compound $\mathrm{Cr}\mathrm{~Cl}_3 \cdot 4 \mathrm{H}_2 0$ precipitates silver chloride when treated with silver nitrate. The molar conductance of its solution corresponds to a total of two ions. Write structural formula of the compound and name it.
Formation of white precipitate with $\mathrm{AgNO}_3$ shows that atleast one Cl ion is present outside the coordination sphere. Moreover only two ions are obtained in solution, so only one $\mathrm{Cl}^{-}$is present outside the sphere. Thus, the formula of the complex is $\left[\mathrm{Co}\left(\mathrm{H}_2\right)_4 \mathrm{Cl}_2\right] \mathrm{Cl}$ and its IUPAC name is Tetraaquadichloridocobalt (III) chloride.
A complex of the type $\left[M(A A)_2 X_2\right]^{n+}$ is known to be optically active. What does this indicate about the structure of the complex? Give one example of such complex.
An optically active complex of the type $\left[M(A A)_2 X_2\right]^{++}$indicates cis-octahedral structure, e.g., cis- $\left[\mathrm{Pt}(\mathrm{en})_2 \mathrm{Cl}_2\right]^{2+}$ or cis- $\left[\mathrm{Cr}(\mathrm{en})_2 \mathrm{Cl}_2\right]^{+}$because its mirror image isomers are non-superimposable.
Non-superimposable isomers of $\left[\mathrm{Pt}(\mathrm{en})_2 \mathrm{Cl}_2\right]^{2+}$.
Magnetic moment of $\left[\mathrm{MnCl}_4\right]^{2-}$ is 5.92 BM . Explain giving reason present.
The magnetic moment 5.92 BM shows that there are five unpaired electrons present in the $d$-orbitals of $\mathrm{Mn}^{2+}$ ion. As a result, the hybridisation involved is $s p^3$ rather than $d s p^2$. Thus tetrahedral structure of $\left[\mathrm{MnCl}_4\right]^{2-}$ complex will show 5.92 BM magnetic moment value.