Sand Bath

A sand bath is a common piece of laboratory equipment made from a container filled with heated sand. It is used to provide even heating for another container, most often during a chemical reaction.

A sand bath is most commonly used in conjunction with a hot plate or heating mantle. A beaker is filled with sand or metal pellets (called shot) and is placed on the plate or mantle. The reaction vessel is then partially covered by sand or pellets. The sand or shot then conducts the heat from the plate to all sides of the reaction vessel.

This technique allows a reaction vessel to be heated throughout with minimal stirring, as opposed to heating the bottom of the vessel and waiting for convection to heat the remainder, cutting down on both the duration of the reaction and the possibility of side reactions that may occur at higher temperatures.

A variation on this theme is the water bath in which the sand is replaced with water. It can be used to keep a reaction vessel at the temperature of boiling water until all water is evaporated (see Standard enthalpy change of vaporization).

Sand baths are one of the oldest known pieces of laboratory equipment, having been used by the alchemists. In Arabic alchemy, a sand bath was known as a qadr. In Latin alchemy, a sand bath was called balneum siccum, balneum cineritium, or balneum arenosum.

Read more about Sand Bath:  See Also

Famous quotes containing the words sand and/or bath:

    This sand seemed to us the connecting link between land and water. It was a kind of water on which you could walk, and you could see the ripple-marks on its surface, produced by the winds, precisely like those at the bottom of a brook or lake. We had read that Mussulmans are permitted by the Koran to perform their ablutions in sand when they cannot get water, a necessary indulgence in Arabia, and we now understand the propriety of this provision.
    Henry David Thoreau (1817–1862)

    For a parent, it’s hard to recognize the significance of your work when you’re immersed in the mundane details. Few of us, as we run the bath water or spread the peanut butter on the bread, proclaim proudly, “I’m making my contribution to the future of the planet.” But with the exception of global hunger, few jobs in the world of paychecks and promotions compare in significance to the job of parent.
    Joyce Maynard (20th century)