Template:Infobox thorium

Thorium, ₉₀Th

Thorium
Pronunciation	/ˈθɔːriəm/ ​(THOR-ee-əm)
Appearance	silvery, often with black tarnish
Standard atomic weight Ar, std(Th)	232.0377(4)
Thorium in the periodic table
Hydrogen Helium Lithium Beryllium Boron Carbon Nitrogen Oxygen Fluorine Neon Sodium Magnesium Aluminium Silicon Phosphorus Sulfur Chlorine Argon Potassium Calcium Scandium Titanium Vanadium Chromium Manganese Iron Cobalt Nickel Copper Zinc Gallium Germanium Arsenic Selenium Bromine Krypton Rubidium Strontium Yttrium Zirconium Niobium Molybdenum Technetium Ruthenium Rhodium Palladium Silver Cadmium Indium Tin Antimony Tellurium Iodine Xenon Caesium Barium Lanthanum Cerium Praseodymium Neodymium Promethium Samarium Europium Gadolinium Terbium Dysprosium Holmium Erbium Thulium Ytterbium Lutetium Hafnium Tantalum Tungsten Rhenium Osmium Iridium Platinum Gold Mercury (element) Thallium Lead Bismuth Polonium Astatine Radon Francium Radium Actinium Thorium Protactinium Uranium Neptunium Plutonium Americium Curium Berkelium Californium Einsteinium Fermium Mendelevium Nobelium Lawrencium Rutherfordium Dubnium Seaborgium Bohrium Hassium Meitnerium Darmstadtium Roentgenium Copernicium Nihonium Flerovium Moscovium Livermorium Tennessine Oganesson Ce ↑ Th ↓ (Uqq) actinium ← thorium → protactinium
Atomic number (Z)	90
Group	group n/a
Period	period 7
Block	f-block
Element category	f-block
Electron configuration	[Rn] 6d2 7s2
Electrons per shell	2, 8, 18, 32, 18, 10, 2
Physical properties
Phase at STP	solid
Melting point	2023 K ​(1750 °C, ​3182 °F)
Boiling point	5061 K ​(4788 °C, ​8650 °F)
Density (near r.t.)	11.7 g/cm3
Heat of fusion	13.81 kJ/mol
Heat of vaporization	514 kJ/mol
Molar heat capacity	26.230 J/(mol·K)
Vapor pressure P (Pa) 1 10 100 1 k 10 k 100 k at T (K) 2633 2907 3248 3683 4259 5055
Atomic properties
Oxidation states	+1, +2, +3, +4 (a weakly basic oxide)
Electronegativity	Pauling scale: 1.3
Ionization energies	1st: 587 kJ/mol 2nd: 1110 kJ/mol 3rd: 1930 kJ/mol
Atomic radius	empirical: 179.8 pm
Covalent radius	206±6 pm
Spectral lines of thorium
Other properties
Natural occurrence	primordial
Crystal structure	​face-centered cubic (fcc)
Speed of sound thin rod	2490 m/s (at 20 °C)
Thermal expansion	11.0 µm/(m·K) (at 25 °C)
Thermal conductivity	54.0 W/(m·K)
Electrical resistivity	157 nΩ·m (at 0 °C)
Magnetic ordering	paramagnetic
Magnetic susceptibility	132.0·10−6 cm3/mol (293 K)
Young's modulus	79 GPa
Shear modulus	31 GPa
Bulk modulus	54 GPa
Poisson ratio	0.27
Mohs hardness	3.0
Vickers hardness	295–685 MPa
Brinell hardness	390–1500 MPa
CAS Number	7440-29-1
History
Naming	after Thor, the Norse god of thunder
Discovery	Jöns Jakob Berzelius (1829)
Main isotopes of thorium
Iso­tope Abun­dance Physics:Half-life (t1/2) Decay mode Pro­duct 227Th trace 18.68 d α 223Ra 228Th trace 1.9116 y α 224Ra 229Th trace 7917 y α 225Ra 230Th 0.02% 75400 y α 226Ra 231Th trace 25.5 h β− 231Pa 232Th 99.98% 1.405×1010 y α 228Ra 234Th trace 24.1 d β− 234Pa

Th data m.p. cat
	in	calc from C	diff	report	ref
C	1750	—	—
K	2023	2020	3
F	3182	3180	2
max precision	0
WD
input	C: 1750, K: 2023, F: 3182
comment

Th data b.p. cat
	in	calc from C	diff	report	ref
C	4788	—	—
K	5061	5061	0
F	8650	8650	0
max precision	0
WD
input	C: 4788, K: 5061, F: 8650
comment

PTChemistry:thorium

Ac ← i'box Ac	iso90Th  infobox  isobox	→ Pa i'box Pa
Commons  Wikidata:Q1115  Wiktionary Indexes in PT: § below · Page

[]  Data sets read by {{Infobox element}}
Name and identifiers
Top image (caption, alt)
Pronunciation
Category (enwiki)
Standard atomic weight
most stable isotope
Natural occurrence
Phase at STP
Chemistry:Oxidation states
Spectral lines image
Physics:Electron configuration (cmt, ref)
Term symbol * (cmt, ref)
Wikidata *
* Not used in {{Infobox element}} (2019-02-03) See also {{Infobox element/symbol-to--navbox}}

References

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