Surfactant Surfactant Surfactants are compounds that lower the surface tension (or interfacial tension) between two liquids, between a gas and a liquid, or between a liquid and a solid. Surfactants may act as detergents, wetting agents, emulsifiers, foaming agents, and dispersants. The term "surfactant" is a blend of "surface active agent". In the United States National Library of Medicine's Medical Subject Headings (MeSH) vocabulary, "surfactant" is reserved for the meaning pulmonary surfactant. For the more general meaning, "surface active agent/s" is the heading. Surfactants are usually organic compounds that are amphiphilic, meaning they contain both hydrophobic groups (their "tails") and hydrophilic
Drop (liquid) by equating the force due to gravity (formula_3) with the component of the surface tension in the vertical direction (formula_4) giving the formula where α is the angle of contact with the tube, and "g" is the acceleration due to gravity. The limit of this formula, as α goes to 90°, gives the maximum weight of a pendant drop for a liquid with a given surface tension, formula_1. This relationship is the basis of a convenient method of measuring surface tension, commonly used in the petroleum industry. More sophisticated methods are available to take account of the developing shape of