Radium nitrate is a radioactive salt with the formula Ra(NO3)2. It is a white solid, but old samples appear yellowish-grey. Although radium chloride and radium bromide are less soluble than the corresponding barium salts, radium nitrate is more soluble than barium nitrate.[1] [2] It decomposes at 280 °C to radium oxide.
Radium nitrate is produced by the reaction of radium carbonate or radium sulfate with nitric acid:[2]
RaCO3 + HNO3 → Ra(NO3)2 + CO2 + H2O