Coordination compounds comprise of molecules or ions coordinated or linked to a transition metal. [Ni(H2O)6]Cl2, [Cr(NH3)5(NO2)]2+ are few examples of coordination compounds. Ag(CN) 2-, CuCl 4 2- are known as coordination complexes or complex ions. Ligands are the molecules or ions that combine with the transition metal ions to produce these complexes. The coordination number of any Coordination compound is the total number of ligands associated with the transition metal ion. Coordination compounds include substances like hemoglobin, chlorophyll, vitamin B12, dyes, and catalysts used in the preparation of organic substances. The Coordination compounds are used as catalysts for several industrial and biological processes that have much importance in the quantitative and qualitative chemical analysis within the field of analytical chemistry.
The important applications of coordination compounds are as follows:
- Due to the formation of cyanide complexes (dicyanoaurate and dicyanoargentate) noble metals like gold and silver are extracted from their ore.
- The hemoglobin is a coordination compound of iron.
- In the polymerization of ethene, The Ziegler Natta catalyst (combination of triethyl aluminum and titanium tetrachloride) is used.
- A complex metal catalyst is used in the hydrogenation of alkenes.
- When aqueous ammonia is mixed with the copper sulphate solution, a deep blue complex soluble in water is formed. This reaction is helpful in detecting cupric ions present in the salt.
The students can easily understand all the important concepts related to this unit by referring to the coordination compounds class 12 notes pdf from the links mentioned below: