Dean Stark apparatus

Learning objectives

To illustrate what the Dean-Stark apparatus consists of, and how it is used.
To illustrate how a Dean Stark apparatus can shift a chemical equilibrium, and so increase the yield of the reaction.
To illustrate the separation of water and ester in order to shift an equilibrium point.

A Dean Stark is a form of glassware used in certain chemical experiments to extract water from a reaction mixture. This apparatus was invented by Ernest W. Dean and David D. Stark in 1920. They described it as "an original method for the determination of the quantity of water and other organic emulsions contained in petroleum".