Bumping (chemistry)
Bumping is a phenomenon in chemistry where homogeneous liquids boiled in a test tube or other container will superheat and, upon nucleation, rapid boiling will expel the liquid from the container. In extreme cases, the container may be broken.[1]
Cause
Bumping occurs when a liquid is heated or has its pressure reduced very rapidly, typically in smooth, clean glassware. The hardest part of bubble formation is the initial formation of the bubble; once a bubble has formed, it can grow quickly. Because the liquid is typically above its boiling point, when the liquid finally starts to boil, a large vapor
Prevention
The most common way of preventing bumping is by adding one or two
A sealed capillary tube can also be placed in a boiling solution to provide a nucleation site, reducing the bumping risk and allowing its easy removal from a system.[3]
Stirring a liquid also lessens the chances of bumping, as the resulting vortex breaks up any large bubbles that might form, and the stirring itself creates bubbles.
References
- ^ "Proper Heating of Test Tubes". CR Scientific LLC. Retrieved 30 October 2010.
- ^ Moya-Barrios, Reinaldo (2015). CHEM 2401 Lab Manual. Dalhousie University Chemistry Department.
- ISBN 978-0-470-64789-9.