Cooling & Heating
Perhaps the most common types of electrical equipment found in a laboratory are the devices used to supply the heat needed to affect a reaction or separation. These include ovens, hot plates, heating mantles, water baths, oil baths, tubular furnaces. The use of steam-heated devices rather than electrically heated devices is generally preferred whenever temperatures of 100 °C or less are required. Because they do not present shock or spark risks, they can be left unattended with assurance that their temperature will never exceed 100 °C. Laboratory heating and cooling equipment is used to sterilize instruments or provide a controlled environment for temperature-sensitive materials.
PRINCIPLES OF HEAT TRANSFER
Conduction is heat transfer by means of molecular agitation within a material without any motion of the material as a whole.
Convection is heat transfer by mass motion of a fluid such as air or water when the heated fluid is caused to move away from the source of heat, carrying energy with it.
Heat transfer due to emission of electromagnetic waves is known as thermal radiation.