Question

Write the important postulates of Werner’s Theory of Coordination Compounds

Answer 1

Werner’s theory of co-ordination

1. Co-ordination compounds show 2 types of linkage (valencies) – primary and secondary

2. The primary valencies are normally ionisable and are satisfied by negative ions.

3. The secondary valencies are non-ionisable.

These are satisfied by neutral molecules or negative ions. The secondary valency is equal to the co-ordination number and is fixed for a metal.

4. The ions/groups bound by the secondary linkages to the metal have characteristic spatial arrangements corresponding to different co-ordination number.