The strength of a molecule's dipole moment directly shapes its bulk physical characteristics, particularly its dielectric constant, the measure of a substance's capacity to reduce the electrostatic forces between charged particles dissolved within it.
| Molecule | Dipole Moment (D) | Dielectric Constant (20°C, 25°C) | Classification | Primary Mechanism |
|---|---|---|---|---|
| Water ($\text{H}_2\text{O}$) | 1.85 | 78.4, 80.1 | Polar Protic | Extensive hydrogen bonding network; dissolves ionic lattices |
| Dimethyl Sulfoxide ($\text{DMSO}$) | 3.96 | 46.7 | Polar Aprotic | Solvates cations while leaving nucleophilic anions exposed |
| Ethanol ($\text{C}_2\text{H}_5\text{OH}$) | 1.69 | 24.5 | Polar Protic | Amphiphilic solvency; bridges aqueous and organic phases |
| Hexane ($\text{C}_6\text{H}_{14}$) | 0.00 | 1.88, 1.89 | Nonpolar Hydrocarbon | London dispersion forces only; extracts lipids and nonpolar oils |
| Methane ($\text{CH}_4$) | 0.00 | 1.70 (liquid, 91 K) | Cryogenic Nonpolar | Dominates Titan's surface hydrology; excludes classic electrolytes |
