Chemicool
Th
90
232.0381
Thorium
General
|
States
|
Energies
|
Oxidation & Electrons
|
Appearance & Characteristics
Reactions
|
Other Forms
|
Radius
|
Conductivity
|
Abundance
Encyclopedia Britannica articles
General
Name
Thorium
Symbol
Th
atomic number
90
Atomic weight
232.0381
Density @ 293 K
11.7 g/cm3
Atomic volume
19.9 cm3/mol
Group
Rare Earth, Actinides
discovered
1829
States
state (s, l, g)
s
melting point
2023.2 K
boiling point
5123 K
Heat of fusion
16.10 kJ/mol
Heat of vaporization
514.40 kJ/mol
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Energies
1st ionization energy
587 kJ/mole
electronegativity
1.3
2nd ionization energy
1110 kJ/mole
electron affinity
kJ/mole
3rd ionization energy
1930 kJ/mole
Specific heat
0.12 J/gK
heat atomization
576 kJ/mole atoms
Oxidation & Electrons
Shells
2,8,18,32,18,10,2
electron configuration
[Rn] 6d2 7s2
minimum oxidation number
0
maximum oxidation number
4
min. common oxidation no.
0
max. common oxidation no.
4
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Appearance & Characteristics
structure
fcc: face-centered cubic
color
white
uses
gas mantles (ThO2)
toxicity
hardness
mohs
characteristics
Radioactive
Reactions
reaction with air
mild, w/ht ignites = ThO2
reaction with 6M HCl
mild
reaction with 6M HCl
mild
reaction with 15M HNO3
passivated
reaction with 6M NaOH
none
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Other Forms
number of isotopes
3
hydride(s)
ThH2 Th4H15
oxide(s)
ThO2
chloride(s)
ThCl4
Radius
ionic radius (2- ion)
pm
ionic radius (1- ion)
pm
atomic radius
179 pm
ionic radius (1+ ion)
pm
ionic radius (2+ ion)
pm
ionic radius (3+ ion)
pm
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Conductivity
thermal conductivity
54 J/m-sec-deg
electrical conductivity
76.923 1/mohm-cm
polarizability
32.1 A^3
Abundance
source
Monazite(phosphate),U extractn
rel. abund. solar system
-1.475 log
abundance earth's crust
1 log
cost, pure
$/100g
cost, bulk
$/100g
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