Cesium chromate is a caesium and hexavalent chromium chemical compound. It has the formula Cs2CrO4 and is an inorganic compound. It is a yellow crystalline solid that crystallizes in the orthorhombic system and is the caesium salt of chromic acid. It is used to make vacuum tubes.

Its primary application in the past was the generation of caesium vapour during the fabrication of vacuum tubes. It is currently only used as a precursor to other compounds of academic interest. It is oxidized, soluble in water, but insoluble in alcohol. It is used in the reaction with silicon, boron, or titanium to produce caesium vapour.

Properties

Chemical formula: Cs2CrO4

Appearance: Yellow crystalline solid

Density: 4.237 g/cm3

Melting point: 954 to 961 °C (1,749 to 1,762 °F; 1,227 to 1,234 K)

Solubility in water: 45.50 g/100 g (25 °C)

Crystal structure: orthorhombic

Applications

Cesium chromate is used to create cesium vapor through a reaction with silicon, boron, or titanium, which is then used in the final stages of vacuum tube manufacturing. It is used in the manufacture of phototubes.

Caesium chromate was previously used in the final stages of vacuum tube manufacturing. Caesium vapour was produced in this study by reacting caesium chromate with silicon, boron, or titanium as reducing agents. After that, the vapour was added to the tube to react with and remove any remaining gases, such as nitrogen and oxygen.