Residue (chemistry)

In chemistry, residue has different meanings. The more common meanings are: the remains or contaminant after a chemical process of preparation, separation, or purification (e.g., distillation, evaporation, or filtration; it may also denote the undesired by-products of a chemical reaction, which are a concern, for example, in agricultural and food industries. Other meanings include functional groups, and the monomers that make up a polymer.