In the complex acetylbromidodicarbonylbis(triethylphosphine)iron$(II)$,the number of $Fe-C$ bond$(s)$ is

The coordination numbers of $Fe$ in the complexes $[Fe(CN)_6]^{4-}$,$[Fe(CN)_6]^{3-}$,and $[FeCl_4]^{-}$ are respectively:

Which of the following metal ions forms a complex with $CN^-$ having a coordination number of $2$?

The oxidation state and covalency of $Al$ in $[AlCl(H_2O)_5]^{2+}$ respectively are

When $AgNO_3$ is added to an aqueous solution of a platinum complex,$1/4$ of the total chlorine content is precipitated. Determine the formula of the platinum complex from the given options.

Select the correct statements about the $PtCl_4 \cdot 4NH_3$ complex salt:
$I.$ All the chlorides are bonded by primary valency.
$II.$ All the chlorides are bonded by secondary valency.
$III.$ All the $NH_3$ are bonded by secondary valency.
$IV.$ Half of the chlorides are bonded with secondary valency.