Answer: donor atom.
- A donor atom
- B counter ion
- C spectator atom
- D bridging unit
Correct answer: A. donor atom
Explanation: The ligand atom that donates the electron pair and is directly attached to the metal is the donor atom, e.g. N in NH<sub>3</sub> or C in CN<sup>-</sup>.
The three common coordination geometries: octahedral (6 ligands), tetrahedral (4 ligands), and square planar (4 ligands in one plane).
Concept context
Study of compounds where a central metal atom is bonded to surrounding ligands. Covers nomenclature, types of isomerism, bonding theories (VBT, CFT), and applications in medicine, photography, and industry.