 | |
| Identifiers | |
|---|---|
3D model (JSmol) | |
| |
| |
| Properties | |
| PoCl2 | |
| Molar mass | 279.91 g/mol |
| Appearance | ruby-red solid[1] |
| Density | 6.50 g cm−3[2] |
| Melting point | 355 °C (671 °F; 628 K) (sublimes at 130 °C)[1] |
| Structure | |
| orthorhombic,oP3[2] | |
| Pmmm (No 47) | |
a = 0.367 nm,b = 0.435 nm,c = 0.450 nm | |
Except where otherwise noted, data are given for materials in theirstandard state (at 25 °C [77 °F], 100 kPa). | |
Polonium dichloride is achemical compound of the radioactivemetalloid,polonium andchlorine. Itschemical formula isPoCl2. It is an ionic salt.
Polonium dichloride appears to crystallise with an orthorhombicunit cell in either theP222,Pmm2 orPmmmspace group, although this is likely a pseudo-cell. Alternatively, the true space group may be monoclinic or triclinic, with one or more cell angles close to 90°.[2] Assuming the space group isP222, the structure exhibits distorted cubic coordination of Po as{PoCl8} and distorted square planar coordination of Cl as{ClPo4}.
PoCl2 can be obtained either byhalogenation of polonium metal or by dehalogenation ofpolonium tetrachloride,PoCl4.[1] Methods for dehalogenatingPoCl4 include thermal decomposition at 300 °C, reduction of cold, slightly moistPoCl4 bysulfur dioxide; and heatingPoCl4 in a stream ofcarbon monoxide orhydrogen sulfide at 150 °C.[2]
PoCl2 dissolves in dilutehydrochloric acid to give a pink solution, whichautoxidises to Po(IV).PoCl2 is rapidly oxidised byhydrogen peroxide or chlorine water. Addition ofpotassium hydroxide to the pink solution results in a dark brown precipitate – possibly hydratedPoO orPo(OH)2 – which is rapidly oxidised to Po(IV). With dilutenitric acid,PoCl2 forms a dark red solution followed by a flaky white precipitate of unknown composition.[2]
