Caesium tungstate or cesium tungstate is an inorganic
chemical compound
A chemical compound is a chemical substance composed of many identical molecules (or molecular entities) containing atoms from more than one chemical element held together by chemical bonds. A molecule consisting of atoms of only one element ...
that is notable for forming a very dense liquid in solution. The solution is used in diamond processing, since diamond sinks in it, whereas most other rocks float.
Properties
Caesium tungstate forms colorless
crystals, which are strongly
hygroscopic
Hygroscopy is the phenomenon of attracting and holding water molecules via either absorption or adsorption from the surrounding environment, which is usually at normal or room temperature. If water molecules become suspended among the substance ...
. A
phase transition
In chemistry, thermodynamics, and other related fields, a phase transition (or phase change) is the physical process of transition between one state of a medium and another. Commonly the term is used to refer to changes among the basic states of ...
from orthorhombic to hexagonal crystal system occurs at 536 °C.
Preparation
Caesium tungstate can be obtained by the reaction between
caesium chloride
Caesium chloride or cesium chloride is the inorganic compound with the formula Cs Cl. This colorless salt is an important source of caesium ions in a variety of niche applications. Its crystal structure forms a major structural type where each ...
(CsCl) and
silver tungstate
Silver tungstate is an inorganic tungstate with the chemical formula Ag2WO4. It has been applied in various fields such as photoluminescence, antibacterial action, ozone gas sensors and humidity sensors. It is also used in the electronic and chemi ...
(Ag
2WO
4) or the reaction between
tungstic acid
Tungstic acid refers to hydrated forms of tungsten trioxide, WO3. Both a monohydrate (WO3·H2O) and hemihydrate (WO3·1/2 H2O) are known. Molecular species akin to sulfuric acid, i.e. (HO)2WO2 are not observed.
The solid-state structure of ...
and
caesium hydroxide.
References
Caesium compounds
Tungstates
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