ickepolära

Ickepolära (icke-polära) is a term in chemistry used to describe molecules and substances with little to no permanent electric dipole moment. In practice, this means their electron distribution is either highly symmetrical or their polar bonds cancel, resulting in minimal interaction with external electric fields.

Most icke-polära substances consist of nonpolar covalent bonds such as C–H, C–C, or Si–H, or they have highly symmetrical geometries that cancel dipole moments. Examples include diatomic nitrogen (N2), oxygen (O2), fluorine (F2); methane (CH4), ethane (C2H6), benzene (C6H6), and larger hydrocarbons.

Physical properties commonly associated with nonpolarity include low dielectric constants and low water solubility, with high solubility in nonpolar solvents such as hexane or toluene. Intermolecular forces are dominated by London dispersion forces. Boiling and melting points generally increase with molecular size, but nonpolar compounds often have lower boiling points than polar compounds of comparable molecular weight due to the absence of strong dipole–dipole or hydrogen-bonding interactions.

Applications and environmental aspects: Nonpolar substances are common solvents in organic chemistry and are used in various separation techniques, including chromatography, where partitioning depends on polarity. Environmentally, nonpolar, lipophilic compounds tend to accumulate in fatty tissues.

Determining nonpolarity: The dipole moment, measured in Debye, indicates polarity; a moment near zero suggests nonpolarity. Molecular symmetry can also cause dipole moments to cancel, as in carbon dioxide (CO2), which is linear and nonpolar despite polar bonds.