The transition metal ion that has 'spin -only ' magnetic moment value of 5.96 is

The transition metal ion that has ‘spin-only’' magnetic moment value of 5.916 is

The transition metal ion that has ‘spin-only’' magnetic moment value of 1.73 is

The spin only magnetic moment value of Fe^(+2) is

Name the metal of the 1^(st) row transition series that has zero spin only magnetic moment in its +2 oxidation state.

Why transition metals forms interstitial compounds? Spin only magnetic moment of Cr^(3+) ion is?