Precipitation is also useful to isolate the products of a reaction during workup. Ideally, the product of the reaction is insoluble in the reaction solvent. Thus, it precipitates as it is formed, preferably forming pure crystals. An example of this would be the synthesis of porphyrins in refluxing propionic acid.
Freebase(0.00 / 0 votes)Rate this definition: Cellophane. Cellophane is a thin, transparent sheet made of regenerated cellulose. Its low permeability to air, oils, greases, bacteria and water makes it useful for food packaging.
Medical Definition of XYLENE. : any of three toxic flammable oily isomeric aromatic hydrocarbons C8H10 that are dimethyl homologues of benzene and are usually obtained from petroleum or natural gas distillates; also: a commercial mixture of xylenes used chiefly as a solvent.