Atomic Number | 101 |
---|---|
Atomic Weight | 258 |
Mass Number | 244 |
Group | |
---|---|
Period | 7 |
Block | f |
Protons | 101 p+ |
---|---|
Neutrons | 143 n0 |
Electrons | 101 e- |
Atomic Radius | |
---|---|
Molar Volume | |
Covalent Radius | 173 pm
|
Metallic Radius | |
Ionic Radius | 109.5 pm
|
Crystal Radius | 123.5 pm
|
Van der Waals Radius |
246 pm
|
Density | 10.3 g/cm³
|
Energy | |
Proton Affinity | |
Electron Affinity | |
Ionization Energy | 6.58 eV/particle
|
Heat of Vaporization | |
Heat of Fusion | |
Heat of Formation | |
Electrons | |
Electron Shells | 2, 8, 18, 32, 31, 8, 2 |
Valence Electrons | 2 |
Electron Configuration | [Rn] 5f13 7s2 |
Oxidation States | 2, 3 |
Electronegativity | |
Electrophilicity | |
Phases | |
Phase | Solid |
Gas Phase | |
Boiling Point | |
Melting Point | 1,100.15 K
|
Critical Pressure | |
Critical Temperature | |
Triple Point | |
Visual | |
Color | Colorless
|
Appearance | |
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 | |
Magnetism | |
Type | |
Magnetic Susceptibility (Mass) | |
Magnetic Susceptibility (Molar) | |
Magnetic Susceptibility (Volume) | |
Magnetic Ordering | |
Curie Point | |
Neel Point | |
Structure | |
Crystal Structure | () |
Lattice Constant | |
Lattice Angles | |
Mechanical Properties | |
Hardness | |
Bulk Modulus | |
Shear Modulus | |
Young Modulus | |
Poisson Ratio | |
Speed of Sound | |
Classification | |
Category | Actinides, Actinides |
CAS Group | |
IUPAC Group | |
Glawe Number | 45 |
Mendeleev Number | 38 |
Pettifor Number | 36 |
Geochemical Class | |
Goldschmidt Class | synthetic |
Other | |
Gas Basicity | |
Dipole Polarizability | |
C6 Dispersion Coefficient | |
Allotropes | |
Neutron Cross Section | |
Neutron Mass Absorption | |
Quantum Numbers | 2F7/2 |
Space Group | () |
Stable Isotopes | 0 |
---|---|
Unstable Isotopes | 19 |
Radioactive Isotopes | 19 |
Abundance | Radioactive ☢️ |
---|---|
Relative Atomic Mass | |
Mass Number | 244 |
G-Factor | |
Half Life | 0.36 ± 0.14 s
|
Spin | 3 |
Quadrupole Moment | |
Discovery Year | 2020 |
Parity | + |
Decay Mode | Intensity |
---|---|
α (α emission) | 100% |
β+ (β+ decay; β+ = ϵ + e+) | % |
β+ SF (β+-delayed fission) | 14% |
Abundance | Radioactive ☢️ |
---|---|
Relative Atomic Mass | |
Mass Number | 245 |
G-Factor | |
Half Life | 0.38 ± 0.1 s
|
Spin | 7/2 |
Quadrupole Moment | |
Discovery Year | 1996 |
Parity | - |
Decay Mode | Intensity |
---|---|
α (α emission) | 100% |
β+ (β+ decay; β+ = ϵ + e+) | % |
Abundance | Radioactive ☢️ |
---|---|
Relative Atomic Mass | |
Mass Number | 246 |
G-Factor | |
Half Life | 0.92 ± 0.18 s
|
Spin | 1 |
Quadrupole Moment | |
Discovery Year | 1996 |
Parity | - |
Decay Mode | Intensity |
---|---|
α (α emission) | 100% |
Abundance | Radioactive ☢️ |
---|---|
Relative Atomic Mass | |
Mass Number | 247 |
G-Factor | |
Half Life | 1.19 ± 0.09 s
|
Spin | 7/2 |
Quadrupole Moment | |
Discovery Year | 1981 |
Parity | - |
Decay Mode | Intensity |
---|---|
α (α emission) | 100% |
SF (spontaneous fission) | 0.1% |
Abundance | Radioactive ☢️ |
---|---|
Relative Atomic Mass | |
Mass Number | 248 |
G-Factor | |
Half Life | 7 ± 3 s
|
Spin | |
Quadrupole Moment | |
Discovery Year | 1973 |
Parity |
Decay Mode | Intensity |
---|---|
β+ (β+ decay; β+ = ϵ + e+) | 80% |
α (α emission) | 20% |
β+ SF (β+-delayed fission) | 0.05% |
Abundance | Radioactive ☢️ |
---|---|
Relative Atomic Mass | |
Mass Number | 249 |
G-Factor | |
Half Life | 25.6 ± 0.9 s
|
Spin | 7/2 |
Quadrupole Moment | |
Discovery Year | 1973 |
Parity | - |
Decay Mode | Intensity |
---|---|
α (α emission) | 75% |
β+ (β+ decay; β+ = ϵ + e+) | % |
Abundance | Radioactive ☢️ |
---|---|
Relative Atomic Mass | |
Mass Number | 250 |
G-Factor | |
Half Life | 54 ± 4 s
|
Spin | 2 |
Quadrupole Moment | |
Discovery Year | 1973 |
Parity | - |
Decay Mode | Intensity |
---|---|
β+ (β+ decay; β+ = ϵ + e+) | 93% |
α (α emission) | 7% |
β+ SF (β+-delayed fission) | 0.026% |
Abundance | Radioactive ☢️ |
---|---|
Relative Atomic Mass | |
Mass Number | 251 |
G-Factor | |
Half Life | 4.21 ± 0.23 m
|
Spin | 7/2 |
Quadrupole Moment | |
Discovery Year | 1973 |
Parity | - |
Decay Mode | Intensity |
---|---|
β+ (β+ decay; β+ = ϵ + e+) | % |
α (α emission) | 10% |
Abundance | Radioactive ☢️ |
---|---|
Relative Atomic Mass | |
Mass Number | 252 |
G-Factor | |
Half Life | 2.3 ± 0.8 m
|
Spin | 1 |
Quadrupole Moment | |
Discovery Year | 1973 |
Parity | + |
Decay Mode | Intensity |
---|---|
β+ (β+ decay; β+ = ϵ + e+) | 100% |
α (α emission) | % |
Abundance | Radioactive ☢️ |
---|---|
Relative Atomic Mass | |
Mass Number | 253 |
G-Factor | |
Half Life | 12 ± 8 m
|
Spin | 7/2 |
Quadrupole Moment | |
Discovery Year | 1992 |
Parity | - |
Decay Mode | Intensity |
---|---|
β+ (β+ decay; β+ = ϵ + e+) | 100% |
α (α emission) | 0.7% |
Abundance | Radioactive ☢️ |
---|---|
Relative Atomic Mass | |
Mass Number | 254 |
G-Factor | 0
|
Half Life | 10 ± 3 m
|
Spin | 0 |
Quadrupole Moment | 0
|
Discovery Year | 1970 |
Parity | - |
Decay Mode | Intensity |
---|---|
β+ (β+ decay; β+ = ϵ + e+) | 100% |
α (α emission) | % |
Abundance | Radioactive ☢️ |
---|---|
Relative Atomic Mass | |
Mass Number | 255 |
G-Factor | |
Half Life | 27 ± 2 m
|
Spin | 7/2 |
Quadrupole Moment | |
Discovery Year | 1958 |
Parity | - |
Decay Mode | Intensity |
---|---|
β+ (β+ decay; β+ = ϵ + e+) | 93% |
α (α emission) | 7% |
SF (spontaneous fission) | % |
Abundance | Radioactive ☢️ |
---|---|
Relative Atomic Mass | |
Mass Number | 256 |
G-Factor | |
Half Life | 77.7 ± 1.8 m
|
Spin | 1 |
Quadrupole Moment | |
Discovery Year | 1955 |
Parity | - |
Decay Mode | Intensity |
---|---|
β+ (β+ decay; β+ = ϵ + e+) | 90.8% |
α (α emission) | 9.2% |
SF (spontaneous fission) | 3% |
Abundance | Radioactive ☢️ |
---|---|
Relative Atomic Mass | |
Mass Number | 257 |
G-Factor | |
Half Life | 5.52 ± 0.05 h
|
Spin | 7/2 |
Quadrupole Moment | |
Discovery Year | 1965 |
Parity | - |
Decay Mode | Intensity |
---|---|
ϵ (electron capture) | 85% |
α (α emission) | 15% |
SF (spontaneous fission) | % |
Abundance | Radioactive ☢️ |
---|---|
Relative Atomic Mass | |
Mass Number | 258 |
G-Factor | |
Half Life | 51.59 ± 0.29 d
|
Spin | 8 |
Quadrupole Moment | |
Discovery Year | 1970 |
Parity | - |
Decay Mode | Intensity |
---|---|
α (α emission) | 100% |
β+ (β+ decay; β+ = ϵ + e+) | 0.0015% |
β− (β− decay) | 0.0015% |
Abundance | Radioactive ☢️ |
---|---|
Relative Atomic Mass | |
Mass Number | 259 |
G-Factor | |
Half Life | 1.6 ± 0.06 h
|
Spin | 7/2 |
Quadrupole Moment | |
Discovery Year | 1982 |
Parity | - |
Decay Mode | Intensity |
---|---|
SF (spontaneous fission) | 100% |
α (α emission) | % |
Abundance | Radioactive ☢️ |
---|---|
Relative Atomic Mass | |
Mass Number | 260 |
G-Factor | |
Half Life | 27.8 ± 0.8 d
|
Spin | |
Quadrupole Moment | |
Discovery Year | 1989 |
Parity |
Decay Mode | Intensity |
---|---|
SF (spontaneous fission) | 100% |
α (α emission) | 5% |
ϵ (electron capture) | 5% |
β− (β− decay) | 3.5% |
Abundance | Radioactive ☢️ |
---|---|
Relative Atomic Mass | |
Mass Number | 261 |
G-Factor | |
Half Life | |
Spin | 7/2 |
Quadrupole Moment | |
Discovery Year | |
Parity | - |
Decay Mode | Intensity |
---|---|
α (α emission) | % |
Abundance | Radioactive ☢️ |
---|---|
Relative Atomic Mass | |
Mass Number | 262 |
G-Factor | |
Half Life | |
Spin | |
Quadrupole Moment | |
Discovery Year | |
Parity |
Decay Mode | Intensity |
---|---|
SF (spontaneous fission) | % |
α (α emission) | % |
Mendelevium was discovered by Albert Ghiorso, Glenn T. Seaborg, Gregory R. Choppin, Bernard G. Harvey and Stanley G. Thompson in 1955 at the University of California, Berkeley. It was produced by the bombardment of einsteinium with helium. Mendelevium was identified by chemical analysis in an ion exchange experiment. Named after Dmitri Mendeleev, who created the Periodic Table
Discoverers | G.T.Seaborg, S.G.Tompson, A.Ghiorso, K.Street Jr. |
---|---|
Discovery Location | United States |
Discovery Year | 1955 |
Etymology (Name Origin) | Named in honor of the scientist Dmitri Ivanovitch Mendeleyev, who devised the periodic table. |
Pronunciation | men-deh-LEE-vi-em (English) |
Made by bombarding einsteinium with helium ions.
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 %
|