Atomic Number | 5 |
---|---|
Atomic Weight | 10.81 |
Mass Number | 11 |
Group | 13 |
---|---|
Period | 2 |
Block | p |
Protons | 5 p+ |
---|---|
Neutrons | 6 n0 |
Electrons | 5 e- |
Atomic Radius | 85 pm
|
---|---|
Molar Volume | 4.6 cm³/mol
|
Covalent Radius | 85 pm
|
Metallic Radius | 80 pm
|
Ionic Radius | 1 pm
|
Crystal Radius | 15 pm
|
Van der Waals Radius | 192 pm
|
Density | 2.34 g/cm³
|
Energy | |
Proton Affinity | |
Electron Affinity | 0.279723 eV/particle
|
Ionization Energy | 8.298019 eV/particle
|
Heat of Vaporization | 504.5 kJ/mol
|
Heat of Fusion | 23.6 kJ/mol
|
Heat of Formation | 565 kJ/mol
|
Electrons | |
Electron Shells | 2, 3 |
Valence Electrons | 3 |
Electron Configuration | [He] 2s2 2p1 |
Oxidation States | -5, -1, 0, 1, 2, 3 |
Electronegativity | 2.04
|
Electrophilicity | 1.1470276511768214 eV/particle
|
Phases | |
Phase | Solid |
Gas Phase | |
Boiling Point | 4,273.15 K
|
Melting Point | 2,350.15 K
|
Critical Pressure | |
Critical Temperature | |
Triple Point | |
Visual | |
Color | Black
|
Appearance | black-brown |
Refractive Index | |
Thermodynamic Properties | |
Thermal Conductivity | 27.4 W/(m K)
|
Thermal Expansion | 0.000006 1/K
|
Molar Heat Capacity | 11.087 J/(mol K)
|
Specific Heat Capacity | 1.026 J/(g⋅K)
|
Heat Capacity Ratio (Adiabatic Index) | |
Electrical Properties | |
Type | Insulator |
Electrical Conductivity | 0.0000000001 MS/m
|
Electrical Resistivity | 10,000 m Ω
|
Superconducting Point | |
Magnetism | |
Type | diamagnetic |
Magnetic Susceptibility (Mass) | -0.0000000087 m³/Kg
|
Magnetic Susceptibility (Molar) | -0.0000000000941 m³/mol
|
Magnetic Susceptibility (Volume) | -0.0000214
|
Magnetic Ordering | |
Curie Point | |
Neel Point | |
Structure | |
Crystal Structure | Simple Trigonal (TET) |
Lattice Constant | 8.73 Å
|
Lattice Angles | 1.01334, 1.01334, 1.01334 |
Mechanical Properties | |
Hardness |
9.3 MPa
|
Bulk Modulus | 320 GPa
|
Shear Modulus | |
Young Modulus | |
Poisson Ratio | |
Speed of Sound | 16,200 m/s
|
Classification | |
Category | Metalloids, Metalloids |
CAS Group | IIIB |
IUPAC Group | IIIA |
Glawe Number | 86 |
Mendeleev Number | 81 |
Pettifor Number | 86 |
Geochemical Class | |
Goldschmidt Class | litophile |
Other | |
Gas Basicity | |
Dipole Polarizability | |
C6 Dispersion Coefficient | 99.5 a₀
|
Allotropes | Alpha Rhombohedral Boron, Beta Rhombohedral Boron, Alpha Tetragonal Boron |
Neutron Cross Section | 760
|
Neutron Mass Absorption | 2.4
|
Quantum Numbers | 2P1/2 |
Space Group | 166 (R_3m) |
Stable Isotopes | 2 |
---|---|
Unstable Isotopes | 14 |
Radioactive Isotopes | 13 |
Abundance | Radioactive ☢️ |
---|---|
Relative Atomic Mass | |
Mass Number | 6 |
G-Factor | |
Half Life | |
Spin | 2 |
Quadrupole Moment | |
Discovery Year | |
Parity | - |
Decay Mode | Intensity |
---|---|
2p (2-proton emission) | % |
Abundance | Radioactive ☢️ |
---|---|
Relative Atomic Mass | |
Mass Number | 7 |
G-Factor | |
Half Life | 570 ± 14 ys
|
Spin | 3/2 |
Quadrupole Moment | |
Discovery Year | 1967 |
Parity | - |
Decay Mode | Intensity |
---|---|
p (proton emission) | 100% |
Abundance | Radioactive ☢️ |
---|---|
Relative Atomic Mass | |
Mass Number | 8 |
G-Factor | 0.51775 ± 0.00015
|
Half Life | 771.9 ± 0.9 ms
|
Spin | 2 |
Quadrupole Moment | 0.0643 ± 0.0014
|
Discovery Year | 1950 |
Parity | + |
Decay Mode | Intensity |
---|---|
β+ (β+ decay; β+ = ϵ + e+) | 100% |
β+α (β+-delayed α emission) | 100% |
Abundance | Radioactive ☢️ |
---|---|
Relative Atomic Mass | |
Mass Number | 9 |
G-Factor | |
Half Life | 800 ± 300 zs
|
Spin | 3/2 |
Quadrupole Moment | |
Discovery Year | 1940 |
Parity | - |
Decay Mode | Intensity |
---|---|
p (proton emission) | 100% |
Abundance | 19.65 ± 0.44
|
---|---|
Relative Atomic Mass | |
Mass Number | 10 |
G-Factor | 0.60015453333333 ± 0.00000026666666666667
|
Half Life | |
Spin | 3 |
Quadrupole Moment | 0.0846 ± 0.0002
|
Discovery Year | 1920 |
Parity | + |
Abundance | 80.35 ± 0.44
|
---|---|
Relative Atomic Mass | |
Mass Number | 11 |
G-Factor | 1.792252 ± 0.00000066666666666667
|
Half Life | |
Spin | 3/2 |
Quadrupole Moment | 0.04059 ± 0.0001
|
Discovery Year | 1920 |
Parity | - |
Abundance | Radioactive ☢️ |
---|---|
Relative Atomic Mass | |
Mass Number | 12 |
G-Factor | 1.003 ± 0.001
|
Half Life | 20.2 ± 0.02 ms
|
Spin | 1 |
Quadrupole Moment | 0.0132 ± 0.0003
|
Discovery Year | 1935 |
Parity | + |
Decay Mode | Intensity |
---|---|
β− (β− decay) | 100% |
β−α (β−-delayed α emission) | 0.6% |
Abundance | Radioactive ☢️ |
---|---|
Relative Atomic Mass | |
Mass Number | 13 |
G-Factor | 2.1185333333333 ± 0.00033333333333333
|
Half Life | 17.16 ± 0.18 ms
|
Spin | 3/2 |
Quadrupole Moment | 0.0365 ± 0.0008
|
Discovery Year | 1956 |
Parity | - |
Decay Mode | Intensity |
---|---|
β− (β− decay) | 100% |
β− n (β−-delayed neutron emission) | 0.266% |
Abundance | Radioactive ☢️ |
---|---|
Relative Atomic Mass | |
Mass Number | 14 |
G-Factor | 0.5925 ± 0.0025
|
Half Life | 12.36 ± 0.29 ms
|
Spin | 2 |
Quadrupole Moment | 0.0297 ± 0.0008
|
Discovery Year | 1966 |
Parity | - |
Decay Mode | Intensity |
---|---|
β− (β− decay) | 100% |
β− n (β−-delayed neutron emission) | 6.04% |
2n (2-neutron emission) | % |
Abundance | Radioactive ☢️ |
---|---|
Relative Atomic Mass | |
Mass Number | 15 |
G-Factor | 1.7726666666667 ± 0.01
|
Half Life | 10.18 ± 0.35 ms
|
Spin | 3/2 |
Quadrupole Moment | 0.0379 ± 0.0011
|
Discovery Year | 1966 |
Parity | - |
Decay Mode | Intensity |
---|---|
β− (β− decay) | 100% |
β− n (β−-delayed neutron emission) | 98.7% |
2n (2-neutron emission) | 1.5% |
Abundance | Radioactive ☢️ |
---|---|
Relative Atomic Mass | |
Mass Number | 16 |
G-Factor | 0
|
Half Life | |
Spin | 0 |
Quadrupole Moment | 0
|
Discovery Year | 2000 |
Parity | - |
Decay Mode | Intensity |
---|---|
n (neutron emission) | % |
Abundance | Radioactive ☢️ |
---|---|
Relative Atomic Mass | |
Mass Number | 17 |
G-Factor | 1.7 ± 0.013333333333333
|
Half Life | 5.08 ± 0.05 ms
|
Spin | 3/2 |
Quadrupole Moment | 0.0385 ± 0.0015
|
Discovery Year | 1973 |
Parity | - |
Decay Mode | Intensity |
---|---|
β− (β− decay) | 100% |
β− n (β−-delayed neutron emission) | 63% |
2n (2-neutron emission) | 12% |
3n (3-neutron emission) | 3.5% |
4n | 0.4% |
Abundance | |
---|---|
Relative Atomic Mass | |
Mass Number | 18 |
G-Factor | |
Half Life | |
Spin | 2 |
Quadrupole Moment | |
Discovery Year | 2010 |
Parity | - |
Decay Mode | Intensity |
---|---|
n (neutron emission) | 100% |
Abundance | Radioactive ☢️ |
---|---|
Relative Atomic Mass | |
Mass Number | 19 |
G-Factor | |
Half Life | 2.92 ± 0.13 ms
|
Spin | 3/2 |
Quadrupole Moment | |
Discovery Year | 1984 |
Parity | - |
Decay Mode | Intensity |
---|---|
β− (β− decay) | 100% |
β− n (β−-delayed neutron emission) | 71% |
2n (2-neutron emission) | 17% |
3n (3-neutron emission) | 9.1% |
Abundance | Radioactive ☢️ |
---|---|
Relative Atomic Mass | |
Mass Number | 20 |
G-Factor | |
Half Life | |
Spin | 1 |
Quadrupole Moment | |
Discovery Year | 2018 |
Parity | - |
Decay Mode | Intensity |
---|---|
n (neutron emission) | 100% |
β− n (β−-delayed neutron emission) | % |
2n (2-neutron emission) | % |
Abundance | Radioactive ☢️ |
---|---|
Relative Atomic Mass | |
Mass Number | 21 |
G-Factor | |
Half Life | |
Spin | 3/2 |
Quadrupole Moment | |
Discovery Year | 2018 |
Parity | - |
Decay Mode | Intensity |
---|---|
2n (2-neutron emission) | 100% |
Boron compounds have been known for thousands of years, but the element was not discovered until 1808 by Sir Humphry Davy and by Gay-Lussac and Thenard. Boron was not recognized as an element until it was isolated in 1808 by Sir Humphry Davy and by Joseph Louis Gay-Lussac and Louis Jacques Thénard. Jöns Jakob Berzelius identified boron as an element in 1824. From the Arabic word Buraq, Persian Burah
Discoverers | Sir H. Davy, J.L. Gay-Lussac, L.J. Thénard |
---|---|
Discovery Location | England/France |
Discovery Year | 1808 |
Etymology (Name Origin) | From Arabic and Persian words for borax. |
Pronunciation | BO-ron (English) |
Obtained from kernite, a kind of borax (Na2B4O7.10H2O). High purity boron is produced by electrolysis of molten potassium fluroborate and potassium chloride (KCl).
Abundance | |
---|---|
Abundance in Earth's crust | 10 mg/kg
|
Abundance in Oceans | 4.44 mg/L
|
Abundance in Human Body | 0.00007 %
|
Abundance in Meteor | 0.00016 %
|
Abundance in Sun | 0.0000002 %
|
Abundance in Universe | 0.0000001 %
|
1 | s | 0.3205 |
2 | p | 2.5786 |
2 | s | 2.4238 |