polonium

• Description
• General information
• Physical data
• Radii
• Electronegativities
• Solid state structure
• Temperatures
• Enthalpies
• Ionization Enthalpies
• Isotopes
• Further information

Description

Polonium has more isotopes than any other element, all of which are radioactive. Polonium dissolves readily in dilute acids, but is only slightly soluble in alkalis.

Weight for weight it is about 2.5 x 10¹¹ times as toxic as hydrocyanic acid (HCN). Polonium has been found in tobacco as a contaminant and in uranium ores.

General information

Discoveror: Marie Curie
Date discovered: 1898
Discovered at: France
Meaning of name: Named after "Poland" (birthplace of Marie Curie)

Physical data

Standard state: solid at 298 K
Colour: silvery
Density of solid at ambient temperature/kg m^-3: 9196
Molar volume/cm³: 22.97

Radii /pm

Atomic: 135
Covalent (single bond):
Pauling radius for the ion [Po]^-: no data

Valence shell orbital radius maxima (R_max)

orbital	s	p	d	f
radius	108.8	126.9	52.4	17.5

Electronegativities

Both values are quoted on the Pauling scale.

Pauling: 2.0
Allred Rochow: 1.76

Crystal Structure

structure: cubic

The following CrystalMaker image represents the solid state structure. For most elements, the most stable allotrope is illustrated. Try WebElements version 2 for interactive virtual reality and CHIME images.

Temperatures (/K)

melting point: 527
boiling point: 1235

Enthalpies /kJ mol^-1

fusion: 13
vaporization: 111

single bond enthalpies:

Po-F	Po-Cl	Po-Br	Po-I	Po-Po
no data	no data	no data	no data	187

Ionization enthalpies /kJ mol^-1

Number	Enthalpy
1st	812

Isotopes

This section gives some data for naturally occurring isotopes.

Nominal mass	Accurate mass	% natural abundance
		nil

Further Information

• Additional information about WebElements 1.2.2
• This is a licensed copy (here is the full list) of WebElements 1.2.2 and contains a subset of the material contained within the main version of WebElements (version 2)
• For further information please try WebElements version 2
• Sheffield Chemdex: perhaps the largest internet chemistry directory
• Sheffield Chemputer: interactive chemistry calculators on the WWW