Answer: Equatorial positions have only 2 nearby 90° interactions, vs 3 for axial positions.
- A Equatorial positions have only 2 nearby 90° interactions, vs 3 for axial positions
- B The axial bond positions are generally geometrically longer overall under most conditions encountered
- C Equatorial bonds are inherently shorter than axial bonds in this geometry as frequently observed in practice
- D PCl<sub>5</sub>'s perfect symmetry makes every position energetically identical in many documented cases
Correct answer: A. Equatorial positions have only 2 nearby 90° interactions, vs 3 for axial positions
Explanation: Axial positions have 3 adjacent equatorial positions at 90° (more repulsion); equatorial positions have only 2 axial neighbours at 90°.
VSEPR theory predicts molecular shape from the number of bonding and lone electron pairs around the central atom.
Concept context
Understand how atoms join to form molecules. Covers ionic and covalent bonding, VSEPR theory, hybridization (sp, sp², sp³), molecular orbital theory, bond polarity, and intermolecular forces like hydrogen bonding.
Read the full Chemical Bonding and Molecular Structure notes →