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.
A cello is a large stringed instrument, related to the viola, violin, double bass, and bass violin. The name cello is a shortening of violoncello, and is sometimes written with an apostrophe as âcello. The cello is usually played with a bow, as the violin, although it may also be plucked. The earliest origins of the cello date back to the mid-16th century, when a three-stringed bass violin was created. For the next hundred years a number of pieces were composed for this instrument, which was usually meant to be played in concert with a violin. In the mid-17th century, with the advent of metal-wrapped strings, an instrument much more like the modern cello was created.