Heating: Does Rate Matter?

Does the rate at which you heat a substance matter? Such as heating an element to its evaportation point or boiling point in a few seconds.
- Anonymous
TSU

Genearlly speaking, heating rates do affect what happens. For example, if you heat a glass very quickly, thermal stresses between different parts of it may cause it to crack. If you heat water quickly to above its boiling point, it may become significantly superheated (staying liquid even above the boiling point) so that when it does start to boil it can boil explosively. The general point is that it takes a while for things to reach internal thermal equilibrium, so if they are heated too fast the can fall out of equilibrium, so different things happen than would happen in equilibrium.

Mike W.

(published on 10/22/2007)