So42 Molecular Geometry «LATEST · Version»

The molecular geometry of the sulfate ion is a classic, beautiful example of how VSEPR theory, resonance, and experimental data converge. It is a perfectly symmetric, tetrahedral anion with four equivalent S–O bonds, a bond angle of 109.5°, and no lone pairs on sulfur. Understanding this geometry is essential for any student of chemistry, as it explains the ion’s stability, its spectroscopic signature, its crystal chemistry, and its pervasive role in natural and industrial processes. Remember: think tetrahedron, not octahedron; think resonance, not fixed double bonds; and think 109.5°, not 90° or 120°. Master SO₄²⁻, and you've mastered a cornerstone of molecular geometry.

Introduction: The Ubiquitous Anion

| Feature | Assessment | | :--- | :--- | | | Tetrahedral | | Molecular Geometry | Tetrahedral | | Bond Angle | 109.5° (ideal) | | Bond Order | 1.5 (resonance hybrid) | | Hybridization (S) | sp³ | | Point Group | Td (highly symmetric) | | Polarity | Nonpolar (symmetrical) | | Common Mistake | Drawing S=O and S–O separately | so42 molecular geometry