Radium sulfate

Radium sulfate
Identifiers
3D model (JSmol)
ChemSpider
  • InChI=1S/H2O4S.Ra/c1-5(2,3)4;/h(H2,1,2,3,4);/p-2
    Key: XOROGAYSRYIXBN-UHFFFAOYSA-L
  • [O-]S(=O)(=O)[O-].[Ra]
Properties
O4RaS
Molar mass 322 g·mol−1
Appearance White solid
3.66×10−11[2]
Related compounds
Other cations
strontium sulfate, barium sulfate, lead(II) sulfate
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).

Radium sulfate (or radium sulphate) is an inorganic compound with the formula RaSO4 and an average molecular mass of 322.088 g/mol.[3] This white salt is the least soluble of all known sulfate salts.[4] It was formerly used in radiotherapy and smoke detectors, but this has been phased out in favor of less hazardous alternatives.

Properties

Radium sulfate crystallizes in a solid in the same structure as barium sulfate. It forms crystals in the orthorhombic crystal system, with a unit cell of dimensions a = 9.13 b=5.54 and c = 7.31 Å. The unit cell volume is 369.7 Å3.[5] Distance from the radium ion to oxygen is 2.96  Å and the sulfur to oxygen bond length in the sulfate ion is 1.485  Å. In this compound the ionic radius of the radium ion is 1.66 Å, and it is in ten coordination.[6]

Radium sulfate can form solid solutions with the sulfates of strontium, barium or lead.[6]

References

  1. ^ Chambers, Michael. "ChemIDplus - 7446-16-4 - MXQFUMUIEZBICJ-UHFFFAOYSA-L - Sulfuric acid, radium salt (1:1) - Similar structures search, synonyms, formulas, resource links, and other chemical information". chem.nlm.nih.gov.
  2. ^ John Rumble (June 18, 2018). CRC Handbook of Chemistry and Physics (99 ed.). CRC Press. pp. 5–189. ISBN 978-1138561632.
  3. ^ "Radium sulfate | O4RaS | ChemSpider".
  4. ^ Kirby, H. W.; Salutsky, Murrell L. (1964). The Radiochemistry of Radium (PDF). National Academies Press. p. 12.
  5. ^ Matyskin, Artem V.; Ylmen, Rikard; Lagerkvist, Petra; Ramebäck, Henrik; Ekberg, Christian (2017). "Crystal structure of radium sulfate: An X-ray powder diffraction and density functional theory study". Journal of Solid State Chemistry. 253: 15–20. Bibcode:2017JSSCh.253...15M. doi:10.1016/j.jssc.2017.05.024.{{cite journal}}: CS1 maint: multiple names: authors list (link)
  6. ^ a b Hedström, Hanna; Persson, Ingmar; Skarnemark, Gunnar; Ekberg, Christian (2013-05-22). "Characterization of Radium Sulphate". Journal of Nuclear Chemistry. 2013: 1–4. doi:10.1155/2013/940701.