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Name: Lorie
Status: student
Age: 18
Location: N/A
Country: N/A
Date: 7/14/2003

what is the function of desiccator?


As you may already know, a desiccator is a drying chamber -- usually a sturdy glass container in which materials may be kept in the absence of air or in the presence of a drying agent.

A desiccator is usually designed so the drying agent rests in a lower chamber. Resting on a rim above it is a plate containing holes to enable air circulation and to serve as secure nesting sites on which the samples to be dried (or kept dry) can sit above and out of contact with the agent.

By selecting different drying agents for the lower chamber, the humidity in the desiccator can be adjusted from very moist to bone dry. This will enable samples kept inside to be held at the optimum humidity for the application at hand.

In addition to a simple desiccator as described above, there exists a variant referred to as a "vacuum desiccator." It looks much like the chamber described above. However, this kind of desiccator has an appurtenance on its lid that enables the chamber to be connected to a vacuum pump used to remove the air from inside the chamber. Once pumped down, a valve-like mechanism on the desiccator can be turned to seal it off from the pump and thereby retain the interior vacuum. When the stored samples are required, the valve is rotated to allow entry of air (or an inert atmosphere) thereby making it possible to open the formerly evacuated chamber.

This kind of desiccator is almost always used when the samples to be stored must be kept as dry as possible -- or if the stored samples could be harmed by contact with air.

ProfHoff 699

Lorie Ann,

A desiccator is a vessel (closed container) that keeps the water vapor (moisture) out of a substance that is placed inside the vessel. The material that keeps the water vapor out of the substance is usually silica gel. The silica gel is placed on the bottom of the desiccator. The material that one wants to keep dry is placed on a tray over top of the desiccants. I hope that this answers your question.


Bob Trach

The purpose of a desiccator is to dry or to keep dry some sample that might be unstable or otherwise changed by the presence of liquid water and/or water vapor.

Vince Calder

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