Question

The coordination number of central metal atom in a complex is determined by

• A. the number of ligands around a metal ion bonded by sigma bonds
• B. the number of ligands around a metal ion bonded by $\pi$ bonds
• C. the number of ligands around a metal ion bonded by sigma and $\pi$ bonds both
• D. None of the above

Answer 1

Answer: (A)

The number of atoms of the ligands that are directly bound to the central metal atom or ion by coordinate bond is known as the coordination number of the metal atom or ion.
Coordination number of metal $=$ number of $\sigma$ bonds formed by metal with ligands.