Three moles of $\mathrm{AgCl}$ get precipitated when one mole of an octahedral co-ordination compound with empirical formula ${\mathrm{CrCl}}_3.3{\mathrm{NH}}_3.3{\mathrm{H}}_2\mathrm{O}$ reacts with excess of silver nitrate. The number of chloride ions satisfying the secondary valency of the metal ion is ______ .

In which of the following order the given complex ions are arranged correctly with respect to their decreasing spin only magnetic moment?
(i) ${\left[{\mathrm{FeF}}_6\right]}^{3-}$

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

(iii) ${\left[{\mathrm{NiCl}}_4\right]}^{2-}$

(iv) ${\left[\mathrm{Cu}{\left({\mathrm{NH}}_3\right)}_4\right]}^{2+}$

Given below are two statements:
Statement I : The identification of ${\mathrm{Ni}}^{2+}$ is carried out by dimethyl glyoxime in the presence of ${\mathrm{NH}}_4\mathrm{OH}$.

Statement II :The dimethyl glyoxime is a bidentate neutral ligand.

In the light of the above statements, choose the correct answer from the options given below: