[Co(en)2(CO)2]Br, cobalt has the coordination number 6, four bonds with ethylenediamine and two bonds with CO. en(ethylenediamine) is NH₂CH₂CH₂NH₂, a bidentate ligand coordinating through its nitrogen lone pairs.
[Pt(NH3)4]Cl2, platinum has coordination number 4, four bonds with ammonia.
