How To: Use a Dean Stark apparatus in the chemistry lab

The Interactive Lab Primer (ILP) has been developed as part of the Royal Society of Chemistry Teacher Fellowship Scheme, one of the themes of the Chemistry for Our Future program, and initiative which aims to secure a strong and sustainable future for the chemical sciences in higher education. The aim of the ILP is to address the diverse range of experience and skills students bring with them to a university by offering a resource to support their transition from school to the university chemistry laboratory. The ILP is quite simply a visual guide to common laboratory techniques.

This video tutorial will teach you how to use a Dean Stark apparatus in the chemistry lab. There are many equilibrium reactions that yield water as a co-product where removal of the water as it is produced is necessary to drive the reaction to completion and this is done using a Dean - Stark apparatus. The reaction is carried out under reflux in a solvent which is less dense than water, both immiscible with it and forms an azeotrope. The apparatus allows the water to be separated from the condensed azeotrope preventing it from returning to the reaction mixture.

Always make yourself aware of the hazards associated with the chemicals involved in a practical before you even start. If you ever come across a chemical you do not know the hazard of you must assume that is very hazardous until you find otherwise.