A group of organic chemicals that are analogs of ammonia (NH₃), in which either one, two or three hydrogen atoms of ammonia are replaced by organic radicals. General formulas are: (1) primary amines, RNH₂, (2) secondary amines, R₁R₂NH, (3) tertiary amines, R₁R₂R₃N and quaternary amines, R₁R₂R₃ R₄N⁺X (where X represents an anion). Amines are organic bases (mildly alkaline) and react with acids to form nitrogenous, organic salts. Amines made from fatty acids are emulsifiers and oil-wetting agents for oilfield chemicals.