The coordination number of cobalt in [Co(NH₃)₆]Cl₃ is ________.
- 3
- 4
- 5
- 6
Answer: 6
Coordination number = number of ligand donor atoms bonded to central metal. Here, six NH₃ molecules coordinate to Co³⁺, giving octahedral geometry. Key concept in Werner's theory. [[NCERT Chemistry Class 12]]