Cannabis Ruderalis

Actinium, 89Ac
Actinium sample (31481701837).png
Actinium
Pronunciation/ækˈtɪniəm/ (ak-TIN-ee-əm)
Appearancesilvery-white, glowing with an eerie blue light;[1] sometimes with a golden cast[2]
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

(Uqt)
radiumactiniumthorium
Atomic number (Z)89
Groupgroup n/a
Periodperiod 7
Block  f-block
Electron configuration[Rn] 6d1 7s2
Electrons per shell2, 8, 18, 32, 18, 9, 2
Physical properties
Phase at STPsolid
Melting point1500 K ​(1227 °C, ​2240 °F) (estimated)[2]
Boiling point3500±300 K ​(3200±300 °C, ​5800±500 °F) (extrapolated)[2]
Density (near r.t.)10 g/cm3
Heat of fusion14 kJ/mol
Heat of vaporization400 kJ/mol
Molar heat capacity27.2 J/(mol·K)
Atomic properties
Oxidation states+2, +3 (a strongly basic oxide)
ElectronegativityPauling scale: 1.1
Ionization energies
  • 1st: 499 kJ/mol
  • 2nd: 1170 kJ/mol
  • 3rd: 1900 kJ/mol
  • (more)
Covalent radius215 pm
Color lines in a spectral range
Spectral lines of actinium
Other properties
Natural occurrencefrom decay
Crystal structureface-centered cubic (fcc)
Face-centered cubic crystal structure for actinium
Thermal conductivity12 W/(m⋅K)
CAS Number7440-34-8
History
Discovery and first isolationFriedrich Oskar Giesel (1902, 1903)
Named byAndré-Louis Debierne (1899)
Main isotopes of actinium
Iso­tope Abun­dance Half-life (t1/2) Decay mode Pro­duct
225Ac trace 10 d α 221Fr
226Ac syn 29.37 h β 226Th
ε 226Ra
α 222Fr
227Ac trace 21.772 y β 227Th
α 223Fr
 Category: Actinium
| references
  Data sets read by {{Infobox element}}
Name and identifiers
Top image (caption, alt)
Pronunciation
Allotropes (demo)
Group (demo)
Period (demo)
Block (demo)
Standard atomic weight
  most stable isotope
Natural occurrence
Phase at STP
Oxidation states
Spectral lines image
Electron configuration (cmt, ref)
Wikidata *
Symbol etymology (11 non-trivial)
* Not used in {{Infobox element}} (2021-12-24)
See also Category:Element data sets (53)

References

  1. ^ Wall, Greg (8 September 2003). "C&EN: It's Elemental: The Periodic Table - Actinium". C&EN: It's Elemental: The Periodic Table. Chemical and Engineering News. Retrieved 2 June 2011.
  2. ^ a b c Kirby, Harold W.; Morss, Lester R. (2006). "Actinium". The Chemistry of the Actinide and Transactinide Elements. p. 18. doi:10.1007/1-4020-3598-5_2. ISBN 978-1-4020-3555-5.

Leave a Reply