Answer: It is hexadentate (2 N + 4 O donor atoms) and forms thermodynamically very stable 1:1 chelates with most metal ions.
- A It is hexadentate (2 N + 4 O donor atoms) and forms thermodynamically very stable 1:1 chelates with most metal ions
- B It is generally bidentate, donating through mainly two of its six potential donor atoms according to conventional understanding
- C It is said to bind mainly to transition metal ions and not to any s-block cations in routine practice overall
- D It is said to become notably unstable once the surrounding solution pH rises above 7 in most cases under typical conditions
Correct answer: A. It is hexadentate (2 N + 4 O donor atoms) and forms thermodynamically very stable 1:1 chelates with most metal ions
Explanation: EDTA<sup>4-</sup> is hexadentate with 6 donor atoms; it forms kinetically stable, soluble chelate complexes (log Kf for Ca<sup>2+</sup>: 10.7; Fe<sup>3+</sup>: 25.1) over a wide pH range.
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.