=> x = + Example : In [Co(NH ) Cl] + , let the oxidation number of cobalt is x : The net charge: + = x + ( ) + (- ) => x = + Evaluate yourself : . In the complex, [Pt(NO )(H O)(NH ) ]Br , identify the following i. Central metal atom/ion ii. Ligand(s) and their types iii.
Coordination entity iv. Oxidation number of the central metal ion v. Coordination number Types of complexes: The coordination compounds can be classified into the following types based on (i) the net charge of the complex ion, (ii) kinds of ligands present in the coordination entity. Classification based on the net charge on the complex: A coordination compound in which the complex ion i.
carries a net positive charge is called a cationic complex. Examples: [Ag(NH ) ] + , [Co(NH ) ] + , [Fe(H O) ] + , etc ii. carries a net negative charge is called an anionic complex. Examples: [Ag(CN) ] - , [Co(CN) ] - , [Fe(CN) ] - , etc iii.
bears no net charge, is called a neutral complex. Examples: [Ni(CO) ], [Fe(CO) ] , [Co(NH ) (Cl) ], Classification based on kind of ligands: A coordination compound in which i. the central metal ion/atom is coordinated to only one kind of ligands is called a homoleptic complex. Examples: [Co(NH ) ] + , [Fe(H O) ] + , XII U5 Coordination XII U5 Coordination - - - - ii.
the central metal ion/atom is coordinated to more than one kind of ligands is called a heteroleptic complex. Example, [Co(NH ) Cl] + , [Pt(NH ) Cl )]