View source for Chemistry:Radium sulfate

{{Chembox
| ImageFile    = Radium sulfate.jpg
| Section1       = {{Chembox Identifiers
| CASNo = 7446-16-4
| CASNo_Ref = <ref>{{cite web |last1=Chambers |first1=Michael |title=ChemIDplus - 7446-16-4 - MXQFUMUIEZBICJ-UHFFFAOYSA-L - Sulfuric acid, radium salt (1:1) - Similar structures search, synonyms, formulas, resource links, and other chemical information. |url=https://chem.nlm.nih.gov/chemidplus/rn/7446-16-4 |website=chem.nlm.nih.gov |language=en}}</ref>{{Cascite|changed|CAS}}
| PubChem = 6365199
| ChemSpiderID = 10745681
| StdInChI=1S/H2O4S.Ra/c1-5(2,3)4;/h(H2,1,2,3,4);/p-2
| StdInChIKey = XOROGAYSRYIXBN-UHFFFAOYSA-L
| SMILES = [O-]S(=O)(=O)[O-].[Ra]
 }}
| Section2       = {{Chembox Properties
| Ra=1|S=1|O=4
| SolubilityProduct = 3.66{{e|&minus;11}}<ref name="crc">{{cite book |author1=John Rumble |title=CRC Handbook of Chemistry and Physics |date=June 18, 2018 |publisher=CRC Press |isbn=978-1138561632 |pages=5–189|edition=99 |language=English}}</ref>
| Appearance = White solid
 }}
| Section8       = {{Chembox Related
|OtherCations=[[Chemistry:Strontium sulfate|strontium sulfate]], [[Chemistry:Barium sulfate|barium sulfate]], [[Chemistry:Lead(II) sulfate|lead(II) sulfate]]
}}
}}
'''Radium sulfate''' (or '''radium sulphate''') is an inorganic compound with the formula RaSO<sub>4</sub> and an average molecular mass of 322.088&nbsp;g/mol.<ref>{{Cite web|url=http://www.chemspider.com/Chemical-Structure.10745681.html|title = Radium sulfate &#124; O4RaS &#124; ChemSpider}}</ref> This white salt is the least soluble of all known [[Chemistry:Sulfate|sulfate]] salts.<ref>{{cite book | url = http://library.lanl.gov/cgi-bin/getfile?rc000041.pdf| title = The Radiochemistry of Radium|ref=Kirby | last1 = Kirby | first1 = H. W. | last2 = Salutsky | first2 = Murrell L. | date = 1964 | page= 12|publisher=National Academies Press}}</ref> 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 [[Chemistry:Orthorhombic|orthorhombic]] crystal system, with a unit cell of dimensions ''a'' = 9.13 ''b''=5.54 and ''c'' = 7.31&nbsp;Å. The unit cell volume is 369.7&nbsp;Å<sup>3</sup>.<ref>{{Cite journal |last=Matyskin, Artem V.; Ylmen, Rikard; Lagerkvist, Petra; Ramebäck, Henrik; Ekberg, Christian |title=Crystal structure of radium sulfate: An X-ray powder diffraction and density functional theory study |url=https://www.sciencedirect.com/science/article/pii/S0022459617301925 |journal=Journal of Solid State Chemistry |date= 2017|volume=253 |pages=15–20|doi= 10.1016/j.jssc.2017.05.024|bibcode= 2017JSSCh.253...15M}}</ref> Distance from the radium ion to oxygen is 2.96&nbsp; Å and the sulfur to oxygen bond length in the sulfate ion is 1.485&nbsp; Å. In this compound the ionic radius of the radium ion is 1.66&nbsp;Å, and it is in ten coordination.<ref name=hed>{{cite journal |last1=Hedström |first1=Hanna |last2=Persson |first2=Ingmar |last3=Skarnemark |first3=Gunnar |last4=Ekberg |first4=Christian |title=Characterization of Radium Sulphate |journal=Journal of Nuclear Chemistry |date=2013-05-22 |volume=2013 |pages=1–4 |doi=10.1155/2013/940701|doi-access=free }}</ref>

Radium sulfate can form [[Physics:Solid solution|solid solution]]s with the sulfates of strontium, barium or lead.<ref name=hed/>

== References ==
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{{sulfates}}

[[Category:Radium compounds]]
[[Category:Sulfates]]

{{Sourceattribution|Radium sulfate}}