Above: Heating mantle

There are several means of heating in the laboratory. In the organic laboratories, you used to use a hot plate with an aluminum block. In research labs, oil baths, sand baths or heating mantles are commonly used. Oil baths works fine for most applications but cause an additional fire hazard when paraffin oil is used. In your lab, a heating mantle will probably be the best heating device to use. It consists of a metal wire (on the inside) that heats up when a current is applied. The other part (heat resistant cloth) protects this wire. There are several points to be consider when using a heating mantle:

1. The power input of the heating mantle has to be controlled. Never plug it directly into a wall plug. The heating mantle will burn out rapidly. It is imperative that it is plugged into a variac (power control).

2. The size of the heating mantle has to match the size of the flask. Heating mantles that are too big or too small don't provide a good heat transfer and will the heating mantle to overheat and burn out as well. In some cases, a better heat transfer can be accomplished by addition sand to the heating mantle.