In the complex ion $[Co(CN)_6]^{3-}$,the $Co^{3+}$ ion absorbs radiation of the violet color from the visible spectrum. What will be the color of its aqueous solution?

Discuss briefly,giving an example in each case,the role of coordination compounds in:
$(i)$ biological systems
$(ii)$ medicinal chemistry
$(iii)$ analytical chemistry
$(iv)$ extraction/metallurgy of metals

What metal is present in Wilkinson's catalyst,which is used as a homogeneous catalyst for the hydrogenation of alkenes?

Prussian blue is formed when

Which chelating ligand is used to remove excess $Cu$ poisoning in plants and animals?

In hemoglobin, the metal ion present is: