Actinium Element in Periodic Table | Atomic Number Atomic Mass


Actinium Element:

Actinium Element- Actinium is the first chemical element in the series of fifteen elements, called actinides, named after the leading element Actinium in the series. It is represented by the symbol Ac and its atomic number is 89. In the seventh period, it is preceded by radium and succeeded by thorium. The series of actinides starts with the element Ac and ends with Lawrencium.

Ac is difficult to be isolated because of its similar chemical properties as that of lanthanides which exist predominantly in the combined form of the common uranium ores/minerals. As an alternative method, actinium is prepared in amounts of milligrams by the neutron irradiation of Radium-226 in nuclear reactor.

Actinium differs from lanthanides due its radioactive nature. It is a soft silvery-white metallic element. It reacts quickly with oxygen forming an external coating of oxide which prevents further oxidation. Generally actinium exhibits the oxidation state of +3. However, due to its intense radioactivity, a limited number of compounds are known to be formed. It forms trihalides and oxyhalides with halogens except iodine.

Actinium occurs in nature as a mixture of two radioactive isotopes Ac-227 and Ac-228.

Uses Of Actinium Element:

Actinium has very less commercial or industrial uses due to its high radioactivity and its production in very small amounts. Actinium is used an important source of alpha rays. Actinium- 225 finds application in the field of medicine in the treatment of radiotherapy. Actinium is also used a vital neutron source as it is hundred times more radioactive than radium.


Actinium Element Information:

Discovery year:1902

Discovered by:Friedrich Oskar Giesel

Atomic number: 89

Relative atomic mass: [227]

Electron configuration: [Rn] 6d1 7s2

Block: d-block

Other elements in the same block:

Scandium, Titanium, Vanadium, Chromium, Manganese, Iron, Cobalt, Nickel, Copper, Zinc, Yttrium, Zirconium, Niobium, Molybdenum, Technetium, Ruthenium, Rhodium, Palladium, Silver, Cadmium, LanthanumHafnium, Tantalum, Tungsten, Rhenium, Osmium, Iridium, Platinum, Gold, Mercury, Rutherfordium, Dubnium, Seaborgium, Bohrium, Hassium, Meitnerium, Darmstadtium, Roentgenium and  Copernicium are the elements in the same block.

Period: period 7 

Other elements in the same period:

Francium, Radium, 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 and Oganesson.

Group: group 3

Other elements in the same group:

Scandium, Yttrium and Lanthanum  are the same group elements

Other elements in the same orbital:

Thorium, Protactinium, Uranium, Neptunium, Plutonium, Americium, Curium, Berkelium, Californium, Einsteinium, Fermium, Mendelevium, Nobelium and Lawrencium are the elements in the same orbital.

Allotropes: none

Key isotopes: 227Ac 

Melting point: 1050°C, 1922°F, 1323 K 

Boiling point: 3200°C, 5792°F, 3473 K

Element category:  actinide

Density (g cm−3): 10

CAS number: 7440-34-8

Color: silvery-white

You can know detailed information for each element,

Hydrogen, HeliumLithiumBerylliumBoronCarbonNitrogenOxygenFluorine,  Neon , SodiumMagnesiumAluminiumSiliconPhosphorusSulfurChlorineArgon, PotassiumCalciumScandiumTitaniumVanadiumChromiumManganeseIronCobaltNickelCopperZincGalliumGermaniumArsenicSeleniumBromine, Krypton,  Rubidium, StrontiumYttriumZirconiumNiobiumMolybdenumTechnetiumRutheniumRhodiumPalladiumSilverCadmiumIndiumTinAntimonyTelluriumIodine, Xenon,  Caesium, BariumLanthanum,  CeriumPraseodymiumNeodymiumPromethiumSamariumEuropiumGadoliniumTerbiumDysprosiumHolmiumErbiumThuliumYtterbiumLutetiumHafniumTantalumTungstenRheniumOsmiumIridiumPlatinumGoldMercuryThalliumLeadBismuthPoloniumAstatine, Radon,  Francium, RadiumActiniumThoriumProtactiniumUraniumNeptuniumPlutoniumAmericiumCuriumBerkeliumCaliforniumEinsteiniumFermiumMendeleviumNobeliumLawrenciumRutherfordiumDubniumSeaborgiumBohriumHassiumMeitneriumDarmstadtiumRoentgeniumCoperniciumNihoniumFleroviumMoscoviumLivermoriumTennessine, Oganesson.

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