| Names | |
|---|---|
| IUPAC name Protactinium(IV) oxide | |
| Identifiers | |
3D model (JSmol) | |
| |
| |
| Properties | |
| O2Pa | |
| Molar mass | 263.034 g·mol−1 |
| Appearance | Black crystals |
| Melting point | 2,927 °C (5,301 °F; 3,200 K)[1] |
| Structure | |
| Fluorite (cubic),cF12 | |
| Fm3m, No. 225 | |
a = 544.6 pm[1] | |
| Hazards | |
| NFPA 704 (fire diamond) | |
| Related compounds | |
Othercations | Thorium(IV) oxide Uranium(IV) oxide |
Except where otherwise noted, data are given for materials in theirstandard state (at 25 °C [77 °F], 100 kPa). | |
Protactinium(IV) oxide is a chemical compound with the formulaPaO2. The black oxide is formed by reducingPa2O5 withhydrogen at 1 550 °C. Protactinium(IV) oxide does not dissolve in H2SO4, HNO3, or HCl solutions, but reacts with HF.[2][3]: 195
As protactinium(IV) oxide, like other protactinium compounds, isradioactive, toxic and very rare, it has no known technological use.
