Question

(a) For the complex ${\left[Fe{\left(CN\right)}_6\right]}^{3-}$, write the hybridization type, magnetic character and spin nature of the complex. (Atomic number : $Fe=26$).
(b) Draw one of the geometrical isomers of the complex ${\left[Pt{\left(en\right)}_2{Cl}_2\right]}^{2+}$ which is optically active.

Answer 1

(a) Atomic number of $Fe$ is $26$.

Electronic configuration of $Fe$ = $\left[Ar\right]{3d}^6{4s}^2$

Now, electronic configuration of ${Fe}^{3+}$ = $\left[Ar\right]{3d}^5{4s}^0$

So, its electronics and hybridisation is shown in figure 1.

So, hybridisation is $d^2{sp}^3$. Since, it has an unpaired electron so its magnetic character is paramagnetic. It is low spin complex.

(b). cis isomer of ${\left[Pt{\left(en\right)}_2{Cl}_2\right]}^{2+}$ is optically active which is shown in figure 2.