What is the coordination number of copper in [Cu(en)2]2+?
In [Cu(en)2]2+, each ethane-1,2-diamine (en) is bidentate, contributing 2 donor atoms. Total = 2 × 2 = 4.
Ref: NCERT Class 12 Chemistry > Chapter 5: Coordination Compounds > Topic: Werner's Theory and Definitions - Ligands Coordination Number