(a) (i) $[{CO}({NH}_3)_5({ONO})]^{2+}$ IUPAC : Pentaammine onitrito cobalt (III) ion (ii) ${K}_2[{NiCl}_4]$ potassiumtetra chlornickelate (II) [OR] (b) (i) Chelate complex: A class of coordination or complex compounds consisting of a central metal atom attached through two or more coordinate bonds with ligands in a cyclic or sing structure. Example : EDIA (ii) Heteroleptic complex: Coordination complexes which contain more than one type of ligands. Example: $[{Fe}({NH}_3)_4 {Cl}_2]^{+}$