Chemicool

Am

95

(243)
Americium
General | States | Energies | Oxidation & Electrons |Appearance & Characteristics
Reactions | Other Forms |Radius | Conductivity | Abundance
Encyclopedia Britannica articles

General

Name Americium Symbol Am
atomic number 95 Atomic weight (243)
Density @ 293 K 13.6 g/cm3 Atomic volume 17.86 cm3/mol
Group Rare Earth, Actinides discovered 1944

States

state (s, l, g) s
melting point 1267.2 K boiling point 2873 K
Heat of fusion 14.40 kJ/mol Heat of vaporization ?
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Energies

1st ionization energy 578 kJ/mole electronegativity 1.3
2nd ionization energy kJ/mole electron affinity kJ/mole
3rd ionization energy kJ/mole Specific heat 0.11 J/gK
heat atomization kJ/mole atoms

Oxidation & Electrons

Shells 2,8,18,32,25,8,2 electron configuration [Rn] 5f7 7s2
minimum oxidation number 0 maximum oxidation number 6
min. common oxidation no. 0 max. common oxidation no. 3
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Appearance & Characteristics

structure fcc: face-centered cubic color silvery-white
uses smoke detector toxicity
hardness mohs characteristics Radioactive

Reactions

reaction with air reaction with 6M HCl
reaction with 6M HCl reaction with 15M HNO3
reaction with 6M NaOH
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Other Forms

number of isotopes 0 hydride(s) AmH2 AmH3
oxide(s) AmO Am2O3 AmO2 chloride(s) AmCl2 AmCl3

Radius

ionic radius (2- ion) pm ionic radius (1- ion) pm
atomic radius 173 pm ionic radius (1+ ion) pm
ionic radius (2+ ion) pm ionic radius (3+ ion) 111.5 pm
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Conductivity

thermal conductivity J/m-sec-deg electrical conductivity 1/mohm-cm
polarizability 23.3 A^3

Abundance

source Synthetic rel. abund. solar system log
abundance earth's crust log cost, pure $/100g
cost, bulk $/100g
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