Aktinyo

Actinium,₈₉Ac

Actinium
Pronunciation	/ækˈtɪniəm/​(ak-TIN-ee-əm)
Appearance	silvery-white, glowing with an eerie blue light;sometimes with a golden cast
Mass number	[227]
Actinium in theperiodic 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	n/a
Period	7
Block	f-block
Electron configuration	[Rn] 6d17s2
Electrons per shell	2, 8, 18, 32, 18, 9, 2
Physical properties
PhaseatSTP	solido
Melting point	1500K​(1227 °C, ​2240 °F)(estimated)
Boiling point	3500±300 K ​(3200±300 °C, ​5800±500 °F)(extrapolated)
Density(nearr.t.)	10 g/cm3
Heat of fusion	14kJ/mol
Heat of vaporization	400 kJ/mol
Molar heat capacity	27.2 J/(mol·K)
Atomic properties
Oxidation states	+2,+3(isang matapang na panimulang oksido)
Electronegativity	Pauling scale: 1.1
Ionization energies	1st: 499 kJ/mol 2nd: 1170 kJ/mol 3rd: 1900 kJ/mol (more)
Covalent radius	215pm
Mga linyang espektral ng actinium
Other properties
Natural occurrence	mula sa pagkabulok
Crystal structure	​face-centered cubic(fcc) (cF4)
Lattice constant	a= 531.5 pm (at 20 °C)
Thermal conductivity	12 W/(m⋅K)
CAS Number	7440-34-8
History
Discoveryand first isolation	Friedrich Oskar Giesel(1902, 1903)
Named by	André-Louis Debierne(1899)
Isotopes of actinium
Main isotopes Decay abun­dance half-life(t1/2) mode pro­duct 225Ac trace 9.919 d α 221Fr CD 211Bi 226Ac synth 29.37 h β− 226Th ε 226Ra α 222Fr 227Ac trace 21.772 y β− 227Th α 223Fr

Angactiniumoaktinyo(Kastila:actinio,may sagisag naAc) ay isang radyoaktibong elementong matatagpuan sa mgainang-batonguranyo,at pinanggagalingan ng mgasinag-alpa.Mayroon itongatomikong bilangna 89. Natuklasan ito noong 1899 niAndré-Louis Debierne.Ito ang unang elementonghindi primordiyalna elementong radyoaktibo na unang naibukod o naihiwalay, bagaman napansin din noong dati pa angpolonyo,radyum,atradon,subalit hindi naibukod hanggang sa sumapit ang 1902. Ito ang pinakamatagal naistopo(Ac 227). Mayroon itong kalahating-buhay na 21.7 mga taon. Kabilang sa mga katangian nito ang punto ng pagkatunaw (MP omelting point) na 1,050 °C, punto ng pagkulo (BP oboiling point) na 3,200 °C, espesipikong grabidad (SG ospecific gravity) na humigit-kumulang sa 10.07, atVna 3.Ito ang elementong nagbigay ng pangalan sa seryengaktinido,na isang pangkat ng 15 katulad na mga elementong nasa pagitan ng aktinyo at nglawrenciumsatalaang peryodiko.