Reflux

Many chemical reactions associated with the heating of reaction mixtures in a solvent. Often the reaction is carried out at the boiling point of the solvent used. In order to prevent the solvent from leaving the reaction vessel ( eg round flasks ), a reflux condenser made ​​of glass is placed perpendicular to the apparatus, see Figure. Condense on the cooling surfaces formed by the heating or by the heat of reaction solvent vapors and drops back into the reaction mixture. Tap water as a coolant in the reflux condenser is used are almost always, only at extremely high boiling point solvents having a boiling point above 150 ° C, an air cooling system is in question.

Soxhlet apparatus also included a reflux condenser.

Reflux condenser different types are described in the article laboratory cooler.