Protactinium(IV) oxide is a chemical compound with the formula PaO2. The black oxide is formed by reducing Pa2O5 with hydrogen 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, is radioactive, toxic and very rare, it has no known technological use.
References
^ abChristine Guéneau; Alain Chartier; Paul Fossati; Laurent Van Brutzel; Philippe Martin (2020). "Thermodynamic and Thermophysical Properties of the Actinide Oxides". Comprehensive Nuclear Materials 2nd Ed. 7: 111–154. doi:10.1016/B978-0-12-803581-8.11786-2. ISBN9780081028667. S2CID261051636.