According to Valence Bond Theory, the number of unpaired electrons present in ${\left[{\mathrm{MnCl}}_6\right]}^{3-}, {\left[\mathrm{Fe}(\mathrm{CN}{)}_6\right]}^{3-}$ and ${\left[\mathrm{Co}\left({\mathrm{C}}_2{\mathrm{O}}_4\right)\right]}^{3-},$ respectively, are

The coordination complex ${\left[\mathrm{Cu}{\left({\mathrm{H}}_2\mathrm{O}\right)}_6\right]}^{2+}$ has one unpaired electron, which of the following statements are true?

(i) The complex is octahedral.

(ii) The complex is an outer orbital complex.

(iii) The complex is diamagnetic.

The correct match is

Which of the following molecules/ions can exhibit isomerism:

Here, $\mathrm{en}=1, 2$-di amino ethane.