1. Surface Tension The contraction force per unit length acting on the surface of a liquid is called surface tension, expressed in units of N·m⁻¹. 2. Surface Activity and Surfactants The ability of a substance to reduce the surface tension of a solvent is referred to as surface activity, and substa

Nonionic surfactants refer to surfactants that do not ionize in aqueous solution. Their hydrophilic groups are mainly composed of oxygen-containing groups (typically ether and hydroxyl groups). The lipophilic part of the molecule is derived from higher fatty alcohols, alkylphenols, fatty acids, fatt