Atomic Number | 95 |
---|---|
Atomic Weight | 243 |
Mass Number | 223 |
Group | |
---|---|
Period | 7 |
Block | f |
Protons | 95 p+ |
---|---|
Neutrons | 128 n0 |
Electrons | 95 e- |
Atomic Radius | 175 pm
|
---|---|
Molar Volume | 20.8 cm³/mol
|
Covalent Radius | 166 pm
|
Metallic Radius | |
Ionic Radius | 121 pm
|
Crystal Radius | 135 pm
|
Van der Waals Radius |
244 pm
|
Density | 12 g/cm³
|
Energy | |
Proton Affinity | |
Electron Affinity | |
Ionization Energy | 5.9738 eV/particle
|
Heat of Vaporization | 238.5 kJ/mol
|
Heat of Fusion | 10 kJ/mol
|
Heat of Formation | 284 kJ/mol
|
Electrons | |
Electron Shells | 2, 8, 18, 32, 25, 8, 2 |
Valence Electrons | 2 |
Electron Configuration | [Rn] 5f7 7s2 |
Oxidation States | 2, 3, 4, 5, 6, 7 |
Electronegativity | |
Electrophilicity | |
Phases | |
Phase | Solid |
Gas Phase | |
Boiling Point | |
Melting Point | 1,449.15 K
|
Critical Pressure | |
Critical Temperature | |
Triple Point | |
Visual | |
Color | Silver
|
Appearance | silvery white |
Refractive Index | |
Thermodynamic Properties | |
Thermal Conductivity | |
Thermal Expansion | |
Molar Heat Capacity | |
Specific Heat Capacity | |
Heat Capacity Ratio (Adiabatic Index) | |
Electrical Properties | |
Type | |
Electrical Conductivity | |
Electrical Resistivity | |
Superconducting Point | 0.6 K
|
Magnetism | |
Type | paramagnetic |
Magnetic Susceptibility (Mass) | 0.0000000515 m³/Kg
|
Magnetic Susceptibility (Molar) | 0.00000001251 m³/mol
|
Magnetic Susceptibility (Volume) | 0.000704
|
Magnetic Ordering | |
Curie Point | |
Neel Point | |
Structure | |
Crystal Structure | Simple Hexagonal () |
Lattice Constant | |
Lattice Angles | π/2, π/2, 2 π/3 |
Mechanical Properties | |
Hardness | |
Bulk Modulus | |
Shear Modulus | |
Young Modulus | |
Poisson Ratio | |
Speed of Sound | |
Classification | |
Category | Actinides, Actinides |
CAS Group | |
IUPAC Group | |
Glawe Number | 39 |
Mendeleev Number | 26 |
Pettifor Number | 42 |
Geochemical Class | |
Goldschmidt Class | synthetic |
Other | |
Gas Basicity | |
Dipole Polarizability | |
C6 Dispersion Coefficient | |
Allotropes | |
Neutron Cross Section | 74
|
Neutron Mass Absorption | |
Quantum Numbers | 8S7/2 |
Space Group | 194 (P63/mmc) |
Stable Isotopes | 0 |
---|---|
Unstable Isotopes | 27 |
Radioactive Isotopes | 27 |
Abundance | Radioactive ☢️ |
---|---|
Relative Atomic Mass | |
Mass Number | 223 |
G-Factor | |
Half Life | 10 ± 9 ms
|
Spin | 9/2 |
Quadrupole Moment | |
Discovery Year | 2015 |
Parity | - |
Decay Mode | Intensity |
---|---|
α (α emission) | 100% |
β+ (β+ decay; β+ = ϵ + e+) | % |
Abundance | Radioactive ☢️ |
---|---|
Relative Atomic Mass | |
Mass Number | 224 |
G-Factor | |
Half Life | |
Spin | |
Quadrupole Moment | |
Discovery Year | |
Parity |
Decay Mode | Intensity |
---|---|
α (α emission) | % |
SF (spontaneous fission) | % |
Abundance | Radioactive ☢️ |
---|---|
Relative Atomic Mass | |
Mass Number | 225 |
G-Factor | |
Half Life | |
Spin | 9/2 |
Quadrupole Moment | |
Discovery Year | |
Parity | - |
Decay Mode | Intensity |
---|---|
α (α emission) | % |
SF (spontaneous fission) | % |
Abundance | Radioactive ☢️ |
---|---|
Relative Atomic Mass | |
Mass Number | 226 |
G-Factor | |
Half Life | |
Spin | |
Quadrupole Moment | |
Discovery Year | |
Parity |
Decay Mode | Intensity |
---|---|
α (α emission) | % |
SF (spontaneous fission) | % |
Abundance | Radioactive ☢️ |
---|---|
Relative Atomic Mass | |
Mass Number | 227 |
G-Factor | |
Half Life | |
Spin | 9/2 |
Quadrupole Moment | |
Discovery Year | |
Parity | - |
Decay Mode | Intensity |
---|---|
α (α emission) | % |
SF (spontaneous fission) | % |
Abundance | Radioactive ☢️ |
---|---|
Relative Atomic Mass | |
Mass Number | 228 |
G-Factor | |
Half Life | |
Spin | |
Quadrupole Moment | |
Discovery Year | |
Parity |
Decay Mode | Intensity |
---|---|
α (α emission) | % |
SF (spontaneous fission) | % |
Abundance | Radioactive ☢️ |
---|---|
Relative Atomic Mass | |
Mass Number | 229 |
G-Factor | |
Half Life | 1.8 ± 1.5 s
|
Spin | 5/2 |
Quadrupole Moment | |
Discovery Year | 2015 |
Parity | - |
Decay Mode | Intensity |
---|---|
α (α emission) | 100% |
β+ (β+ decay; β+ = ϵ + e+) | % |
Abundance | Radioactive ☢️ |
---|---|
Relative Atomic Mass | |
Mass Number | 230 |
G-Factor | |
Half Life | 40 ± 9 s
|
Spin | 1 |
Quadrupole Moment | |
Discovery Year | 2003 |
Parity | - |
Decay Mode | Intensity |
---|---|
β+ (β+ decay; β+ = ϵ + e+) | 100% |
β+ SF (β+-delayed fission) | 30% |
Abundance | Radioactive ☢️ |
---|---|
Relative Atomic Mass | |
Mass Number | 231 |
G-Factor | |
Half Life | |
Spin | 5/2 |
Quadrupole Moment | |
Discovery Year | |
Parity | - |
Decay Mode | Intensity |
---|---|
β+ (β+ decay; β+ = ϵ + e+) | % |
α (α emission) | % |
Abundance | Radioactive ☢️ |
---|---|
Relative Atomic Mass | |
Mass Number | 232 |
G-Factor | |
Half Life | 1.31 ± 0.04 m
|
Spin | 1 |
Quadrupole Moment | |
Discovery Year | 1967 |
Parity | - |
Decay Mode | Intensity |
---|---|
β+ (β+ decay; β+ = ϵ + e+) | 97% |
α (α emission) | % |
β+ SF (β+-delayed fission) | 0.069% |
Abundance | Radioactive ☢️ |
---|---|
Relative Atomic Mass | |
Mass Number | 233 |
G-Factor | |
Half Life | 3.2 ± 0.8 m
|
Spin | 5/2 |
Quadrupole Moment | |
Discovery Year | 2000 |
Parity | - |
Decay Mode | Intensity |
---|---|
β+ (β+ decay; β+ = ϵ + e+) | % |
α (α emission) | 4.5% |
Abundance | Radioactive ☢️ |
---|---|
Relative Atomic Mass | |
Mass Number | 234 |
G-Factor | 0
|
Half Life | 2.32 ± 0.08 m
|
Spin | 0 |
Quadrupole Moment | 0
|
Discovery Year | 1967 |
Parity | - |
Decay Mode | Intensity |
---|---|
β+ (β+ decay; β+ = ϵ + e+) | 100% |
α (α emission) | 0.039% |
β+ SF (β+-delayed fission) | 0.0066% |
Abundance | Radioactive ☢️ |
---|---|
Relative Atomic Mass | |
Mass Number | 235 |
G-Factor | |
Half Life | 10.3 ± 0.6 m
|
Spin | 5/2 |
Quadrupole Moment | |
Discovery Year | 1996 |
Parity | - |
Decay Mode | Intensity |
---|---|
β+ (β+ decay; β+ = ϵ + e+) | 99.6% |
α (α emission) | 0.4% |
Abundance | Radioactive ☢️ |
---|---|
Relative Atomic Mass | |
Mass Number | 236 |
G-Factor | |
Half Life | 3.6 ± 0.1 m
|
Spin | 5 |
Quadrupole Moment | |
Discovery Year | 1998 |
Parity | - |
Decay Mode | Intensity |
---|---|
β+ (β+ decay; β+ = ϵ + e+) | 100% |
α (α emission) | 4% |
Abundance | Radioactive ☢️ |
---|---|
Relative Atomic Mass | |
Mass Number | 237 |
G-Factor | |
Half Life | 73.6 ± 0.8 m
|
Spin | 5/2 |
Quadrupole Moment | |
Discovery Year | 1970 |
Parity | - |
Decay Mode | Intensity |
---|---|
β+ (β+ decay; β+ = ϵ + e+) | 99.975% |
α (α emission) | 0.025% |
Abundance | Radioactive ☢️ |
---|---|
Relative Atomic Mass | |
Mass Number | 238 |
G-Factor | |
Half Life | 98 ± 3 m
|
Spin | 1 |
Quadrupole Moment | |
Discovery Year | 1950 |
Parity | + |
Decay Mode | Intensity |
---|---|
β+ (β+ decay; β+ = ϵ + e+) | 100% |
α (α emission) | 1% |
Abundance | Radioactive ☢️ |
---|---|
Relative Atomic Mass | |
Mass Number | 239 |
G-Factor | |
Half Life | 11.9 ± 0.1 h
|
Spin | 5/2 |
Quadrupole Moment | |
Discovery Year | 1949 |
Parity | - |
Decay Mode | Intensity |
---|---|
ϵ (electron capture) | 99.99% |
α (α emission) | 0.01% |
Abundance | Radioactive ☢️ |
---|---|
Relative Atomic Mass | |
Mass Number | 240 |
G-Factor | |
Half Life | 50.8 ± 0.3 h
|
Spin | 3 |
Quadrupole Moment | |
Discovery Year | 1949 |
Parity | - |
Decay Mode | Intensity |
---|---|
β+ (β+ decay; β+ = ϵ + e+) | 100% |
α (α emission) | 1.9% |
Abundance | Radioactive ☢️ |
---|---|
Relative Atomic Mass | |
Mass Number | 241 |
G-Factor | 0.64 ± 0.004
|
Half Life | 432.6 ± 0.6 y
|
Spin | 5/2 |
Quadrupole Moment | 4.34 ± 0.05
|
Discovery Year | 1949 |
Parity | - |
Decay Mode | Intensity |
---|---|
α (α emission) | 100% |
SF (spontaneous fission) | 3.6% |
Abundance | Radioactive ☢️ |
---|---|
Relative Atomic Mass | |
Mass Number | 242 |
G-Factor | 0.3854 ± 0.0017
|
Half Life | 16.02 ± 0.02 h
|
Spin | 1 |
Quadrupole Moment | -2.4 ± 0.4
|
Discovery Year | 1949 |
Parity | - |
Decay Mode | Intensity |
---|---|
β− (β− decay) | 82.7% |
ϵ (electron capture) | 17.3% |
Abundance | Radioactive ☢️ |
---|---|
Relative Atomic Mass | |
Mass Number | 243 |
G-Factor | 0.608 ± 0.004
|
Half Life | 7.35 ± 0.009 ky
|
Spin | 5/2 |
Quadrupole Moment | 4.32 ± 0.06
|
Discovery Year | 1950 |
Parity | - |
Decay Mode | Intensity |
---|---|
α (α emission) | 100% |
SF (spontaneous fission) | 3.7% |
Abundance | Radioactive ☢️ |
---|---|
Relative Atomic Mass | |
Mass Number | 244 |
G-Factor | |
Half Life | 10.01 ± 0.03 h
|
Spin | 6 |
Quadrupole Moment | |
Discovery Year | 1950 |
Parity | - |
Decay Mode | Intensity |
---|---|
β− (β− decay) | 100% |
Abundance | Radioactive ☢️ |
---|---|
Relative Atomic Mass | |
Mass Number | 245 |
G-Factor | |
Half Life | 2.05 ± 0.01 h
|
Spin | 5/2 |
Quadrupole Moment | |
Discovery Year | 1955 |
Parity | + |
Decay Mode | Intensity |
---|---|
β− (β− decay) | 100% |
Abundance | Radioactive ☢️ |
---|---|
Relative Atomic Mass | |
Mass Number | 246 |
G-Factor | |
Half Life | 39 ± 3 m
|
Spin | 7 |
Quadrupole Moment | |
Discovery Year | 1955 |
Parity | - |
Decay Mode | Intensity |
---|---|
β− (β− decay) | 100% |
Abundance | Radioactive ☢️ |
---|---|
Relative Atomic Mass | |
Mass Number | 247 |
G-Factor | |
Half Life | 23 ± 1.3 m
|
Spin | 5/2 |
Quadrupole Moment | |
Discovery Year | 1967 |
Parity |
Decay Mode | Intensity |
---|---|
β− (β− decay) | 100% |
Abundance | Radioactive ☢️ |
---|---|
Relative Atomic Mass | |
Mass Number | 248 |
G-Factor | |
Half Life | |
Spin | 3 |
Quadrupole Moment | |
Discovery Year | |
Parity | + |
Decay Mode | Intensity |
---|---|
β− (β− decay) | % |
Americium-241 was first identified in 1944 by Glenn T. Seaborg, Ralph A. James, Leon O. Morgan and Albert Ghiorso at the metallurgical laboratory at the University of Chicago. It was produced by irradiating plutonium with neutrons during the Manhattan Project. Americium was first isolated as a pure compound by Burris Cunningham in 1945, at the University of Chicago. Named after America
Discoverers | G.T.Seaborg, R.A.James, L.O.Morgan, A.Ghiorso |
---|---|
Discovery Location | United States |
Discovery Year | 1945 |
Etymology (Name Origin) | Named for the American continent, by analogy with europium. |
Pronunciation | am-er-ISH-i-em (English) |
Produced by bombarding plutonium with neutrons.
Abundance | |
---|---|
Abundance in Earth's crust | |
Abundance in Oceans | |
Abundance in Human Body | 0 %
|
Abundance in Meteor | 0 %
|
Abundance in Sun | 0 %
|
Abundance in Universe | 0 %
|