Polonium tetraiodide

Polonium tetraiodide

Names
Other names Polonium(IV) iodide
Identifiers
CAS Number	61716-27-6
3D model (JSmol)	Interactive image
InChI InChI=1S/4HI.Po/h4*1H;/q;;;;+4/p-4 Key: DHKHYWWHNZXEQM-UHFFFAOYSA-J
SMILES I[Po](I)(I)I
Properties
Chemical formula	PoI 4 [1]
Molar mass	716.6 g/mol
Appearance	Black crystals
Melting point	200 °C (392 °F; 473 K)
Solubility in water	Insoluble [2]
Related compounds
Related compounds	Chromium(III) sulfide
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). Infobox references

Polonium tetraiodide is a binary inorganic compound of polonium and iodine with the chemical formula PoI
_⁴. ^{[3] [4]} The compound forms volatile black crystals. ^[5]

Synthesis

1. Action of iodine vapor on polonium metal:

Po + 2 I₂ → PoI₄

2. Dissolution of polonium dioxide in hydroiodic acid: ^[6]

PoO₂ + 4 HI → PoI₄ + 2 H₂O

Properties

Physical properties

The compound forms black crystals that are insoluble in water.

Chemical properties

The compound reacts with hydroiodic acid to form hexaiodopolonic acid:

PoI₄ + 2 HI → H₂[PoI₆]

It can be reduced by hydrogen sulfide to yield polonium metal. ^[5] It decomposes on heating.

References

1. Macintyre, Jane E. (23 July 1992). Dictionary of Inorganic Compounds. CRC Press. p. 3510. ISBN   978-0-412-30120-9 . Retrieved 2 November 2021.
2. Schweitzer, George K.; Pesterfield, Lester L. (14 January 2010). The Aqueous Chemistry of the Elements. Oxford University Press. p. 134. ISBN   978-0-19-539335-4 . Retrieved 2 November 2021.
3. Brown, Susan A.; Brown, Paul L. (25 September 2019). The Aqueous Chemistry of Polonium and the Practical Application of its Thermochemistry. Elsevier. p. 24. ISBN   978-0-12-819309-9 . Retrieved 2 November 2021.
4. Schmidt, M.; Siebert, W.; Bagnall, K.W. (2013). The Chemistry of Sulphur, Selenium, Tellurium and Polonium: Pergamon Texts in Inorganic Chemistry. Elsevier. pp. 961–962. ISBN   978-1483158655.
5. K. W. Bagnall, R. W. M. D'Eye, J. H. Freeman (1956). "657. The polonium halides. Part III. Polonium tetraiodide". Journal of the Chemical Society (Resumed). J. Chem. Soc.: 3385–3389. doi:10.1039/JR9560003385.
6. M. Schmidt, W. Siebert, K. W. Bagnall (2013). The Chemistry of Sulphur, Selenium, Tellurium and Polonium: Pergamon Texts in Inorganic Chemistry. Elsevier. pp. 961–962. ISBN   978-1483158655.