hydrophobicity

chemistry

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June 29, 2026

Quick Summary

Hydrophobicity refers to a lack of affinity for water. In chemistry, this concept is closely related to polarity.1

Polarity describes how electrical charge is distributed across atoms in a chemical bond. When atoms have different electronegativities, they attract electrons unequally, creating partial positive and negative charges on the atoms. This results in a polar bond. Molecules with polar bonds can be polar overall, depending on their shape.

Substances with similar polarities tend to dissolve in each other. Nonpolar substances are often described as "lipid-loving" (lipophilic), while polar substances are "water-loving" (hydrophilic). This principle explains why lipid-soluble, nonpolar molecules can pass through cell membranes, which are largely composed of nonpolar lipids, while many polar molecules cannot.2

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alcohol
Physical properties of alcohols
…of the molecule, which is hydrophobic (“water-hating”), is larger with increased molecular weight. Because they are strongly polar, alcohols are better solvents than hydrocarbons for ionic compounds and other polar substances.
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…of the molecule, which is hydrophobic (“water-hating”), is larger with increased molecular weight. Because they are strongly polar, alcohols are better solvents than hydrocarbons for ionic compounds and other polar substances.
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food additive
Processing agents
…an emulsifying agent includes a hydrophobic portion, usually a long-chain fatty acid, and a hydrophilic portion that may be either charged or uncharged. The hydrophobic portion of the emulsifier dissolves in the oil phase, and the hydrophilic portion dissolves in the aqueous phase, forming a dispersion of small oil droplets.…
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…an emulsifying agent includes a hydrophobic portion, usually a long-chain fatty acid, and a hydrophilic portion that may be either charged or uncharged. The hydrophobic portion of the emulsifier dissolves in the oil phase, and the hydrophilic portion dissolves in the aqueous phase, forming a dispersion of small oil droplets.…
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lipid
Lipids, however, are hydrophobic (“water-fearing”). Some lipids are amphipathic—part of their structure is hydrophilic and another part, usually a larger section, is hydrophobic. Amphipathic lipids exhibit a unique behavior in water: they spontaneously form ordered molecular aggregates, with their hydrophilic ends on the outside, in contact with the…
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Lipids, however, are hydrophobic (“water-fearing”). Some lipids are amphipathic—part of their structure is hydrophilic and another part, usually a larger section, is hydrophobic. Amphipathic lipids exhibit a unique behavior in water: they spontaneously form ordered molecular aggregates, with their hydrophilic ends on the outside, in contact with the…
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anesthetic
Local anesthetics
The hydrophobic nature of the molecules makes it possible for them to penetrate the fatty membrane of the nerve fibres and exert their effects from the inside. When an impulse passes along a nerve, there are transient changes in the properties of the membrane that allow…
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The hydrophobic nature of the molecules makes it possible for them to penetrate the fatty membrane of the nerve fibres and exert their effects from the inside. When an impulse passes along a nerve, there are transient changes in the properties of the membrane that allow…
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