'Desiccation' is the state of extreme dryness, or the process of extreme drying. A
desiccant is a
hygroscopic substance that induces or sustains such a state in its local vicinity in a moderately-well sealed container.
Science

Toluene is refluxed with
sodium and
benzophenone to produce dry, oxygen-free toluene. The toluene is dry and oxygen free when the intense blue coloration from the benzophenone ketyl radical is observed.
Desiccator
In
science, a
desiccator is a heavy
glass or
plastic container used in practical
chemistry for making or keeping small amounts of material very dry. The material is placed on a shelf, and a drying agent or 'desiccant', such as dry
silica gel or anhydrous
caustic soda, is placed below the shelf.
Often some sort of
humidity indicator is included in the desiccator to show, by color changes, the level of humidity. These indicators are in the form of indicator plugs or indicator cards. The active chemical is
cobalt chloride (CoCl
2).
Anhydrous cobalt chloride is blue. When it bonds with two water molecules, (CoCl
2•2H
2O), it turns purple. Further hydration results in the pink hexaaquacobalt(II) chloride complex [Co(H
2O)
6]Cl
2.
Biology and ecology
In
biology and
ecology, 'desiccation' refers to the drying out of a living organism, such as when aquatic animals are taken out of water, or when plants are exposed to sunlight or drought. Ecologists frequently study and assess various organisms' susceptibility to desiccation.
Broadcasting
In
broadcast engineering, a 'desiccator' may be used to
pressurize the
feedline of a high-power transmitter. Because it carries very high
electrical power levels from the
transmitter to the
antenna, the feedline must have a good
dielectric. Because it must also be lightweight so as not to overload the
radio tower, air is often used as the dielectric. Since
moisture can
condense in these lines, desiccated air or
nitrogen gas is pumped in. This
pressure also keeps
water or other
dampness from coming in the line at any point along its length.
See also
★
List of desiccants
★
Hygroscopy
External links
★
Desiccant info
★
Latest US desiccants patents information.
★
A Desiccant Requirements Calculator