What is the total number of ligands present in $[CoCl_{2}(NH_{3})_{4}]Cl$?

Which of the following complexes is homoleptic?

The number of unidentate ligands attached to the central metal ion in a complex is called:

Which of the following is the odd one out?

The oxidation number of iron in the compound formed during the brown ring test for $NO_3^{-}$ ion is . . . . . .

Consider the following complex: $[Co(CO_3)(NH_3)_5]ClO_4$.
Mark the correct option for the following parameters in order:
Coordination number $-$ Oxidation number $-$ Number of $d$-electrons $-$ Number of unpaired $d$-electrons.