Caesium tungstate

Caesium tungstate or cesium tungstate is an inorganic chemical compound 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.

Caesium tungstate

Names
Other names Cesium tungstate, Cesium tungsten oxide
Identifiers
CAS Number	13587-19-4
3D model (JSmol)	Interactive image
ChemSpider	11294571
ECHA InfoCard	100.033.639
EC Number	237-019-0
PubChem CID	22269592
CompTox Dashboard (EPA)	DTXSID50890877
InChI InChI=1S/2Cs.4O.W/q2*+1;;;2*-1; Key: VPXSRGLTQINCRV-UHFFFAOYSA-N
SMILES [O-][W](=O)(=O)[O-].[Cs+].[Cs+]
Properties
Chemical formula	Cs2WO4
Molar mass	513.65 g/mol
Melting point	>350 °C[1]
Related compounds
Other cations	Lithium tungstate Sodium tungstate
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). Infobox references

Properties

Caesium tungstate forms colorless crystals, which are strongly hygroscopic. A phase transition from orthorhombic to hexagonal crystal system occurs at 536 °C.

Preparation

Caesium tungstate can be obtained by the reaction between caesium chloride (CsCl) and silver tungstate (Ag₂WO₄) or the reaction between tungstic acid and caesium hydroxide.