Triuranium octoxide
| Names | |
|---|---|
| Other names
Uranium(V,VI) oxide Pitchblende C.I. 77919 | |
| Identifiers | |
3D model (JSmol) |
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| ChemSpider | |
| ECHA InfoCard | 100.014.275 |
| EC Number |
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PubChem CID |
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CompTox Dashboard (EPA) |
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| Properties | |
| U3O8 | |
| Molar mass | 842.08 g/mol |
| Density | 8.38 g/cm3 |
| Melting point | 1,150 °C (2,100 °F; 1,420 K) |
| Boiling point | decomposes to UO2 at 1,300 °C (2,370 °F; 1,570 K) |
| Insoluble | |
| Solubility | Soluble in nitric acid and sulfuric acid |
| Thermochemistry | |
Std molar entropy (S⦵298) |
282 J·mol−1·K−1 |
Std enthalpy of formation (ΔfH⦵298) |
−3575 kJ·mol−1 |
| Hazards | |
| GHS labelling: | |
| Danger | |
| H300, H330, H373, H411 | |
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
Infobox references | |
Triuranium octoxide (U3O8) is a compound of uranium. It is present as an olive green to black, odorless solid. It is one of the more popular forms of yellowcake and is shipped between mills and refineries in this form.
U3O8 has potential long-term stability in a geologic environment. In the presence of oxygen (O2), uranium dioxide (UO2) is oxidized to U3O8, whereas uranium trioxide (UO3) loses oxygen at temperatures above 500 °C and is reduced to U3O8. The compound can be produced by the calcination of ammonium diuranate or ammonium uranyl carbonate. Due to its high stability, it can be used for the disposal of depleted uranium. Its particle density is 8.38 g cm−3.
Triuranium octoxide is converted to uranium hexafluoride for the purpose of uranium enrichment.