A polar molecule has an uneven distribution of electron density that produces a net molecular dipole. A nonpolar molecule has no lasting net dipole, either because its bonds are only weakly polar or because its bond dipoles cancel through symmetry.
Bond polarity alone is not enough to classify a whole molecule. Carbon dioxide has polar C=O bonds but is linear and symmetric, so their dipoles cancel. Water has polar O–H bonds and a bent geometry, so its dipoles reinforce one another.
How to identify molecular polarity
First identify polar bonds from electronegativity differences, then determine the molecular geometry and ask whether the bond dipoles cancel. Lone pairs often change geometry: ammonia is trigonal pyramidal and polar, while boron trifluoride is trigonal planar and nonpolar despite its polar B–F bonds.
For larger organic molecules, functional groups and molecular shape both matter. Hydroxyl, carbonyl, amide, and charged groups usually increase polarity, while a large hydrocarbon region can dominate the behavior of an otherwise polar functional group.
Reading the dipole moment column
The dipole column gives measured gas-phase dipole moments in debye (D) from the NIST Computational Chemistry Comparison and Benchmark Database. Water measures 1.86 D, ammonia 1.48 D, and hydrogen chloride 1.09 D, while symmetric molecules such as CO₂, BF₃, CCl₄, and SF₆ measure zero.
A few hydrocarbons have small but nonzero dipoles, such as 0.36 D for propene and 0.78 D for propyne. They are still classed as nonpolar because dispersion forces dominate how they behave, and the basis column says so. The cell is left blank where no single experimental value is available, for example for zwitterionic amino acids or molecules whose conformers have different dipoles.
Polarity, solubility, and intermolecular forces
“Like dissolves like” is a useful first approximation: polar solvents tend to dissolve polar or ionic solutes, and nonpolar solvents tend to dissolve nonpolar solutes. It is not an absolute rule because hydrogen bonding, ionization, temperature, and the relative sizes of polar and nonpolar regions also influence solubility.
How this dataset was assembled
Each molecule is classified from bond polarity and molecular geometry, and the Basis column gives the specific reason. Dipole moments are experimental gas-phase values in debye from the NIST CCCBDB compilation, left blank when CCCBDB has no single unambiguous value (for example when conformers differ) or none at all. Simple hydrocarbons are labelled nonpolar even when they have a small measured dipole, and the Basis column says so. Ionic compounds are excluded because molecular polarity applies to discrete molecules.
Each row retains source identifiers where available. Molecular weight is calculated from the recorded formula, and the original names, structures, classifications, and database links remain visible so individual entries can be checked before reuse.
License and citation
This compilation is free to download and reuse under the Creative Commons Attribution 4.0 International license. Credit ProteinIQ and the original sources when you share it or publish results that use it.
Suggested citation: ProteinIQ (2026). List of polar and nonpolar molecules, version 2026.10.05. https://proteiniq.io/datasets/polar-and-nonpolar-molecules
Sources and further reading
PubChem: Canonical compound identifiers, names, formulas, structures, SMILES, and downloadable compound records. NCBI places no restrictions on PubChem data, though original submitters may retain rights in submitted records.
NIST CCCBDB: Experimental gas-phase dipole moments (NIST Computational Chemistry Comparison and Benchmark Database, SRD 101). NIST Standard Reference Database 101; values are cited per row with the CCCBDB reference code.
RDKit: Derived descriptors such as molecular weight, LogP, TPSA, hydrogen-bond counts, and canonicalized structures.
OpenStax Chemistry: Chemistry definitions used for educational polarity, bonding, organic chemistry, and molecule-class explanations.
Frequently asked questions
Draw or determine the molecular geometry, mark the polar bonds, and add their dipoles as vectors. A nonzero result indicates a polar molecule; complete cancellation indicates a nonpolar molecule.
Water is bent, so its O–H bond dipoles do not cancel. Carbon dioxide is linear, so its two equal C=O bond dipoles point in opposite directions and cancel.
Yes. Symmetric molecules such as CO₂, BF₃, CCl₄, and SF₆ have polar bonds whose dipoles cancel across the complete geometry.
Most simple hydrocarbons are treated as nonpolar because C–C bonds are nonpolar and C–H bonds are only weakly polar. Substitution with heteroatoms or charged groups can make an organic molecule polar.
Yes. In cis-1,2-dichloroethylene both C-Cl bonds sit on the same side of the double bond, giving a dipole of about 1.9 D. In the trans isomer they point in opposite directions and cancel, so the molecule is nonpolar.
Yes. Ozone is bent and its central oxygen is bonded differently from the two end oxygens, so electron density is unevenly shared and the molecule has a small dipole of about 0.53 D.