Template:Infobox actinium

Actinium, ₈₉Ac

File:Actinium sample (31481701837).png
Actinium
Pronunciation	/ækˈtɪniəm/ Template:Error-small ​(ak-TIN-ee-əm)
Appearance	silvery-white, glowing with an eerie blue light; sometimes with a golden cast
Mass number	[227]
Actinium 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 La ↑ Ac ↓ — radium ← actinium → thorium
Atomic number (Z)	89
Group	f-block groups (no number)
Period	period 7
Block	f-block
Electron configuration	[Rn] 6d1 7s2
Electrons per shell	2, 8, 18, 32, 18, 9, 2
Physical properties
Phase at STP	solid
Melting point	1500 K ​(1227 °C, ​2240 °F) (estimated)
Boiling point	3500±300 K ​(3200±300 °C, ​5800±500 °F) (extrapolated)
Density (near r.t.)	10 g/cm3
Heat of fusion	14 kJ/mol
Heat of vaporization	400 kJ/mol
Molar heat capacity	27.2 J/(mol·K)
Atomic properties
Oxidation states	common: +3 +2
Electronegativity	Pauling scale: 1.1
Ionization energies	1st: 499 kJ/mol 2nd: 1170 kJ/mol 3rd: 1900 kJ/mol (more)
Covalent radius	215 pm
Color lines in a spectral range Spectral lines of actinium
Other properties
Natural occurrence	from decay
Crystal structure	​face-centered cubic (fcc) (cF4)
Lattice constant	Face-centered cubic crystal structure for actinium a = 531.5 pm (at 20 °C)
Thermal conductivity	12 W/(m⋅K)
CAS Number	7440-34-8
History
Naming	from the Ancient Greek ακτίς, "beam" or "ray"
Discovery	Friedrich Oskar Giesel (1902)
First isolation	Joseph G. Stites, Murrell L. Salutsky, Bob D. Stone (1955)
Named by	André-Louis Debierne (1899)
Isotopes of actinium
Main isotopes Decay Isotope abun­dance half-life (t1/2) mode pro­duct 225Ac trace 9.919 d α 221Fr 226Ac synth 29.37 h β− 226Th ε 226Ra α 222Fr 227Ac trace 21.772 y β− 227Th α 223Fr 228Ac trace 6.15 h β− 228Th

Ac · Actinium
Ra ← ibox Ra	iso 89 Ac  [] IB-Ac [] IBisos []	→ Th ibox Th
File:Symbol category class.svg cat:Ac (0) File:Symbol category class.svg cat:Ac-isotopes (0)  Commons  Wikidata:Q1121 File:Wiktionary-logo.svg Wiktionary
indexes by PT (page)

child table, as reused in {IB-Ac}
Main isotopes of actinium
Main isotopes Decay Isotope abun­dance half-life (t1/2) mode pro­duct 225Ac trace 9.919 d α 221Fr 226Ac synth 29.37 h β− 226Th ε 226Ra α 222Fr 227Ac trace 21.772 y β− 227Th α 223Fr 228Ac trace 6.15 h β− 228Th

Data sets read by {{Infobox element}}
Name and identifiers
Symbol etymology (11 non-trivial)
Top image (caption, alt)	caption: alt:
Pronunciation
Allotropes (overview)
Group (overview)
Period (overview)
Block (overview)
Natural occurrence
Phase at STP
Oxidation states
Spectral lines image
Electron configuration (cmt, ref)
Isotopes
Standard atomic weight
most stable isotope
File:Notification-icon-Wikidata-logo.svg Wikidata
Wikidata *
* Not used in {{Infobox element}} (2023-01-01) See also {{Index of data sets}} · Cat:data sets (0) · (this table: )

References

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