HHomeBackground Color:He
LiBeAmericium Main PageBlack White GrayBCNOFNe
NaMgAmericium Pictures PageAlSiPSClAr
KCaAmericium Isotope DataScTiVCrMnFeCoNiCuZnGaGeAsSeBrKr
RbSrYZrNbMoTcRuRhPdAgCdInSnSbTeIXe
CsBaLaCePrNdPmSmEuGdTbDyHoErTmYbLuHfTaWReOsIrPtAuHgTlPbBiPoAtRn
FrRaAcThPaUNpPuAmCmBkCfEsFmMdNoLrRfDbSgBhHsMtDsRgCnNhFlMcLvTsOg

Technical data for Americium

Click any property name to see plots of that property for all the elements.

Overview
NameAmericium
SymbolAm
Atomic Number95
Atomic Weight243[note]
Density13.67 g/cm3
Melting Point1176 °C
Boiling Point2011 °C

Thermal properties
PhaseSolid
Melting Point1176 °C
Boiling Point2011 °C
Absolute Melting Point1449 K
Absolute Boiling Point2284 K
Critical PressureN/A
Critical TemperatureN/A
Heat of FusionN/A
Heat of VaporizationN/A
Specific HeatN/A
Adiabatic IndexN/A
Neel PointN/A
Thermal Conductivity10 W/(m K)
Thermal ExpansionN/A

Bulk physical properties
Density13.67 g/cm3
Density (Liquid)N/A
Molar Volume0.00001777615215801
Brinell HardnessN/A
Mohs HardnessN/A
Vickers HardnessN/A
Bulk ModulusN/A
Shear ModulusN/A
Young ModulusN/A
Poisson RatioN/A
Refractive IndexN/A
Speed of SoundN/A
Thermal Conductivity10 W/(m K)
Thermal ExpansionN/A

Reactivity
Valence4
Electronegativity1.3
ElectronAffinityN/A
Ionization Energies
578 kJ/mol

Health and Safety
DOT Hazard ClassN/A
DOT NumbersN/A
RTECS NumberN/A
NFPA LabelN/A

Classifications
Alternate NamesNone
Names of AllotropesNone
Blockf
GroupN/A
Period7
SeriesActinide
Electron Configuration[Rn]7s25f7
ColorSilver
Discovery
1944 in The United States
Gas phaseN/A
CAS NumberCAS7440-35-9
CID NumberN/A
RTECS NumberN/A

Electrical properties
Electrical TypeN/A
Electrical ConductivityN/A
ResistivityN/A
Superconducting Point0.6

Magnetic properties
Magnetic TypeParamagnetic
Curie PointN/A
Mass Magnetic Susceptibility5.15×10-8 m3/Kg
Molar Magnetic Susceptibility1.251×10-8 m3/mol
Volume Magnetic Susceptibility0.000704

Abundances
% in UniverseN/A
% in Sun0%
% in Meteorites0%
% in Earth's Crust0%
% in Oceans0%
% in Humans0%

Atomic dimensions and structure
Atomic RadiusN/A
Covalent Radius180 pm
Van der Waals RadiusN/A
Crystal StructureSimple Hexagonal
Lattice Angles
π/2, π/2, 2 π/3
Lattice Constants
346.81, 346.81, 1124.1 pm
Space Group NameP63/mmc
Space Group Number194

Nuclear Properties
Half-Life7388.381532217 y
Lifetime10654.49010654 y
Decay ModeAlphaEmission
Quantum Numbers8S7/2
Neutron Cross Section74
Neutron Mass AbsorptionN/A
Known Isotopes
231Am, 232Am, 233Am, 234Am, 235Am, 236Am, 237Am, 238Am, 239Am, 240Am, 241Am, 242Am, 243Am, 244Am, 245Am, 246Am, 247Am, 248Am, 249Am
Stable Isotopes
None
Isotopic Abundances


Notes on the properties of Americium:

Atomic Mass: Atomic mass number given for longest lived isotope.

Up to date, curated data provided by Mathematica's ElementData function from Wolfram Research, Inc.

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