Atomic Number | 18 |
---|---|
Atomic Weight | 39.948 |
Mass Number | 40 |
Group | 18 |
---|---|
Period | 3 |
Block | p |
Protons | 18 p+ |
---|---|
Neutrons | 22 n0 |
Electrons | 18 e- |
Atomic Radius | |
---|---|
Molar Volume | |
Covalent Radius | |
Metallic Radius | |
Ionic Radius | |
Crystal Radius | |
Van der Waals Radius | |
Density |
Energy | |
---|---|
Proton Affinity | |
Electron Affinity | |
Ionization Energy | |
Heat of Vaporization | |
Heat of Fusion | |
Heat of Formation | |
Electrons | |
Electron Shells | 2, 8, 8 |
Valence Electrons | 8 ⓘ |
Electron Configuration | [Ne] 3s2 3p6ⓘ 1s2 2s2 2p6 3s2 3p6 |
Oxidation States | 0 |
Electronegativity | |
Electrophilicity Index | |
States of Matter | |
Phase | Gas |
Gas Phase | Monoatomic |
Boiling Point | |
Melting Point | |
Critical Pressure | |
Critical Temperature | |
Triple Point | |
Visual | |
Argon is a Colorless. Ar has a CPK of #ff1493, Jmol of #80d1e3, and MOLCAS GV of #80d1e3. The Appearance of Element 18 is colorless gas exhibiting a lilac/violet glow when placed in a high voltage electric field. The Refractive Index of Argon (Ar) is 1.000281. | |
Color | Colorless
|
Appearance | colorless gas exhibiting a lilac/violet glow when placed in a high voltage electric field |
Refractive Index | 1.000281
|
Thermodynamic Properties | |
Thermal Conductivity | |
Thermal Expansion | |
Molar Heat Capacity | |
Specific Heat Capacity | |
Heat Capacity Ratio (Adiabatic Index) | 5/3 |
Electrical Properties | |
Type | |
Electrical Conductivity | |
Electrical Resistivity | |
Superconducting Point | |
Magnetism | |
Type | diamagnetic |
Magnetic Susceptibility (Mass) | -0.000000006 m³/Kg
|
Magnetic Susceptibility (Molar) | -0.00000000024 m³/mol
|
Magnetic Susceptibility (Volume) | -0.0000000107
|
Magnetic Ordering | |
Curie Point | |
Neel Point | |
Structure | |
The Crystal Structure of Argon is FCC. The lattice constant of Ar is 5.26 Å. The lattice angles of Element 18 are π/2, π/2, π/2. | |
Crystal Structure | Face Centered Cubic (FCC) |
Lattice Constant | |
Lattice Angles | π/2, π/2, π/2 |
Mechanical Properties | |
The Speed of Sound of Argon is 319 m/s. | |
Hardness | |
Bulk Modulus | |
Shear Modulus | |
Young's Modulus | |
Poisson Ratio | |
Speed of Sound | |
Classification | |
The CAS Group of Argon is VIII. The IUPAC Group of Ar is VIIIA. The Glawe Number of Element 18 is 3. The Mendeleev Number of Argon (Ar) is 114. The Pettifor Number of Argon is 3. The Geochemical Class of Ar is volatile. The Goldschmidt Class of Element 18 is atmophile. | |
Category | Noble gases, Noble gases |
CAS Group | VIII |
IUPAC Group | VIIIA |
Glawe Number | 3 |
Mendeleev Number | 114 |
Pettifor Number | 3 |
Geochemical Class | volatile |
Goldschmidt Class | atmophile |
The Gas Basicity of Argon is 346.3 kJ/mol. The Dipole Polarizability of Ar is 11.083 plus or minus 0.007 a₀. Element 18 has a C6 Dispersion Coefficient (CD) of 64.2 a₀, and C6 Dispersion Coefficient (GB) of 67.4 a₀. The Allotropes of Argon (Ar) is . The Neutron Cross Section of Argon is 0.66. The Neutron Mass Absorption of Ar is 0.00059. The Quantum Numbers of Element 18 is 1S0. The Space Group of Argon (Ar) is 225 (Fm_3m).
Gas Basicity | |
---|---|
Dipole Polarizability | |
C6 Dispersion Coefficient | |
Allotropes | |
Neutron Cross Section | 0.66
|
Neutron Mass Absorption | 0.00059
|
Quantum Numbers | 1S0 |
Space Group | 225 (Fm_3m) |
Stable Isotopes | 2 |
---|---|
Unstable Isotopes | 24 |
Natural Isotopes | 3 |
Mass Number | 29 |
---|---|
Neutron Number | 11 |
Relative Atomic Mass | |
G-Factor | |
Abundance | |
Radioactivity | ☢️ Radioactive |
Half Life | |
Spin | 5/2 |
Quadrupole Moment | |
Discovery Year | 2018 |
Parity | + |
Decay Mode | Intensity |
---|---|
2p (2-proton emission) | 100% |
Mass Number | 30 |
---|---|
Neutron Number | 12 |
Relative Atomic Mass | |
G-Factor | 0
|
Abundance | |
Radioactivity | ☢️ Radioactive |
Half Life | |
Spin | 0 |
Quadrupole Moment | 0
|
Discovery Year | 2015 |
Parity | + |
Decay Mode | Intensity |
---|---|
2p (2-proton emission) | 100% |
Mass Number | 31 |
---|---|
Neutron Number | 13 |
Relative Atomic Mass | |
G-Factor | |
Abundance | |
Radioactivity | ☢️ Radioactive |
Half Life | 15 ± 0.3 ms
|
Spin | 5/2 |
Quadrupole Moment | |
Discovery Year | 1986 |
Parity | + |
Decay Mode | Intensity |
---|---|
β+ (β+ decay; β+ = ϵ + e+) | 100% |
β+ p (β+-delayed proton emission) | 68.3% |
2p (2-proton emission) | 9% |
B+pA | 0.38% |
3p | 0.07% |
β+α (β+-delayed α emission) | 0.03% |
2p (2-proton emission) | 0.0006% |
Mass Number | 32 |
---|---|
Neutron Number | 14 |
Relative Atomic Mass | |
G-Factor | 0
|
Abundance | |
Radioactivity | ☢️ Radioactive |
Half Life | 98 ± 2 ms
|
Spin | 0 |
Quadrupole Moment | 0
|
Discovery Year | 1977 |
Parity | + |
Decay Mode | Intensity |
---|---|
β+ (β+ decay; β+ = ϵ + e+) | 100% |
β+ p (β+-delayed proton emission) | 35.58% |
Mass Number | 33 |
---|---|
Neutron Number | 15 |
Relative Atomic Mass | |
G-Factor | -1.446 ± 0.012
|
Abundance | |
Radioactivity | ☢️ Radioactive |
Half Life | 173 ± 2 ms
|
Spin | 1/2 |
Quadrupole Moment | 0
|
Discovery Year | 1964 |
Parity | + |
Decay Mode | Intensity |
---|---|
β+ (β+ decay; β+ = ϵ + e+) | 100% |
β+ p (β+-delayed proton emission) | 38.7% |
Mass Number | 34 |
---|---|
Neutron Number | 16 |
Relative Atomic Mass | |
G-Factor | 0
|
Abundance | |
Radioactivity | ☢️ Radioactive |
Half Life | 846.46 ± 0.35 ms
|
Spin | 0 |
Quadrupole Moment | 0
|
Discovery Year | 1966 |
Parity | + |
Decay Mode | Intensity |
---|---|
β+ (β+ decay; β+ = ϵ + e+) | 100% |
Mass Number | 35 |
---|---|
Neutron Number | 17 |
Relative Atomic Mass | |
G-Factor | 0.42133333333333 ± 0.00013333333333333
|
Abundance | |
Radioactivity | ☢️ Radioactive |
Half Life | 1.7756 ± 0.001 s
|
Spin | 3/2 |
Quadrupole Moment | -0.084 ± 0.015
|
Discovery Year | 1940 |
Parity | + |
Decay Mode | Intensity |
---|---|
β+ (β+ decay; β+ = ϵ + e+) | 100% |
Mass Number | 36 |
---|---|
Neutron Number | 18 |
Relative Atomic Mass | |
G-Factor | 0
|
Abundance | 0.3336 ± 0.021
|
Radioactivity | ☢️ Radioactive |
Half Life | |
Spin | 0 |
Quadrupole Moment | 0
|
Discovery Year | 1920 |
Parity | + |
Decay Mode | Intensity |
---|---|
2β+ (double β+ decay) |
Mass Number | 37 |
---|---|
Neutron Number | 19 |
Relative Atomic Mass | |
G-Factor | |
Abundance | |
Radioactivity | ☢️ Radioactive |
Half Life | 35.011 ± 0.019 d
|
Spin | 3/2 |
Quadrupole Moment | 0.076 ± 0.003
|
Discovery Year | 1941 |
Parity | + |
Decay Mode | Intensity |
---|---|
ϵ (electron capture) | 100% |
Mass Number | 38 |
---|---|
Neutron Number | 20 |
Relative Atomic Mass | |
G-Factor | 0
|
Abundance | 0.0629 ± 0.007
|
Radioactivity | Stable |
Half Life | Not Radioactive ☢️ |
Spin | 0 |
Quadrupole Moment | 0
|
Discovery Year | 1934 |
Parity | + |
Mass Number | 39 |
---|---|
Neutron Number | 21 |
Relative Atomic Mass | |
G-Factor | -0.45428571428571 ± 0.0042857142857143
|
Abundance | |
Radioactivity | ☢️ Radioactive |
Half Life | 268 ± 8 y
|
Spin | 7/2 |
Quadrupole Moment | -0.116 ± 0.002
|
Discovery Year | 1950 |
Parity | - |
Decay Mode | Intensity |
---|---|
β− (β− decay) | 100% |
Mass Number | 40 |
---|---|
Neutron Number | 22 |
Relative Atomic Mass | |
G-Factor | 0
|
Abundance | 99.6035 ± 0.025
|
Radioactivity | Stable |
Half Life | Not Radioactive ☢️ |
Spin | 0 |
Quadrupole Moment | 0
|
Discovery Year | 1920 |
Parity | + |
Mass Number | 41 |
---|---|
Neutron Number | 23 |
Relative Atomic Mass | |
G-Factor | -0.37428571428571 ± 0.0022857142857143
|
Abundance | |
Radioactivity | ☢️ Radioactive |
Half Life | 109.61 ± 0.04 m
|
Spin | 7/2 |
Quadrupole Moment | -0.042 ± 0.004
|
Discovery Year | 1936 |
Parity | - |
Decay Mode | Intensity |
---|---|
β− (β− decay) | 100% |
Mass Number | 42 |
---|---|
Neutron Number | 24 |
Relative Atomic Mass | |
G-Factor | 0
|
Abundance | |
Radioactivity | ☢️ Radioactive |
Half Life | 32.9 ± 1.1 y
|
Spin | 0 |
Quadrupole Moment | 0
|
Discovery Year | 1952 |
Parity | + |
Decay Mode | Intensity |
---|---|
β− (β− decay) | 100% |
Mass Number | 43 |
---|---|
Neutron Number | 25 |
Relative Atomic Mass | |
G-Factor | -0.4088 ± 0.0024
|
Abundance | |
Radioactivity | ☢️ Radioactive |
Half Life | 5.37 ± 0.06 m
|
Spin | 5/2 |
Quadrupole Moment | 0.142 ± 0.014
|
Discovery Year | 1969 |
Parity |
Decay Mode | Intensity |
---|---|
β− (β− decay) | 100% |
Mass Number | 44 |
---|---|
Neutron Number | 26 |
Relative Atomic Mass | |
G-Factor | 0
|
Abundance | |
Radioactivity | ☢️ Radioactive |
Half Life | 11.87 ± 0.05 m
|
Spin | 0 |
Quadrupole Moment | 0
|
Discovery Year | 1969 |
Parity | + |
Decay Mode | Intensity |
---|---|
β− (β− decay) | 100% |
Mass Number | 45 |
---|---|
Neutron Number | 27 |
Relative Atomic Mass | |
G-Factor | |
Abundance | |
Radioactivity | ☢️ Radioactive |
Half Life | 21.48 ± 0.15 s
|
Spin | 5/2 |
Quadrupole Moment | |
Discovery Year | 1974 |
Parity | - |
Decay Mode | Intensity |
---|---|
β− (β− decay) | 100% |
Mass Number | 46 |
---|---|
Neutron Number | 28 |
Relative Atomic Mass | |
G-Factor | 0
|
Abundance | |
Radioactivity | ☢️ Radioactive |
Half Life | 8.4 ± 0.6 s
|
Spin | 0 |
Quadrupole Moment | 0
|
Discovery Year | 1974 |
Parity | + |
Decay Mode | Intensity |
---|---|
β− (β− decay) | 100% |
Mass Number | 47 |
---|---|
Neutron Number | 29 |
Relative Atomic Mass | |
G-Factor | |
Abundance | |
Radioactivity | ☢️ Radioactive |
Half Life | 1.23 ± 0.03 s
|
Spin | 3/2 |
Quadrupole Moment | |
Discovery Year | 1985 |
Parity |
Decay Mode | Intensity |
---|---|
β− (β− decay) | 100% |
β− n (β−-delayed neutron emission) | 0.2% |
Mass Number | 48 |
---|---|
Neutron Number | 30 |
Relative Atomic Mass | |
G-Factor | 0
|
Abundance | |
Radioactivity | ☢️ Radioactive |
Half Life | 415 ± 15 ms
|
Spin | 0 |
Quadrupole Moment | 0
|
Discovery Year | 2004 |
Parity | + |
Decay Mode | Intensity |
---|---|
β− (β− decay) | 100% |
β− n (β−-delayed neutron emission) | 38% |
Mass Number | 49 |
---|---|
Neutron Number | 31 |
Relative Atomic Mass | |
G-Factor | |
Abundance | |
Radioactivity | ☢️ Radioactive |
Half Life | 236 ± 8 ms
|
Spin | 3/2 |
Quadrupole Moment | |
Discovery Year | 1989 |
Parity | - |
Decay Mode | Intensity |
---|---|
β− (β− decay) | 100% |
β− n (β−-delayed neutron emission) | 29% |
2n (2-neutron emission) |
Mass Number | 50 |
---|---|
Neutron Number | 32 |
Relative Atomic Mass | |
G-Factor | 0
|
Abundance | |
Radioactivity | ☢️ Radioactive |
Half Life | 106 ± 6 ms
|
Spin | 0 |
Quadrupole Moment | 0
|
Discovery Year | 1989 |
Parity | + |
Decay Mode | Intensity |
---|---|
β− (β− decay) | 100% |
β− n (β−-delayed neutron emission) | 37% |
2n (2-neutron emission) |
Mass Number | 51 |
---|---|
Neutron Number | 33 |
Relative Atomic Mass | |
G-Factor | |
Abundance | |
Radioactivity | ☢️ Radioactive |
Half Life | |
Spin | 1/2 |
Quadrupole Moment | 0
|
Discovery Year | 1989 |
Parity | - |
Decay Mode | Intensity |
---|---|
β− (β− decay) | |
β− n (β−-delayed neutron emission) | |
2n (2-neutron emission) |
Mass Number | 52 |
---|---|
Neutron Number | 34 |
Relative Atomic Mass | |
G-Factor | 0
|
Abundance | |
Radioactivity | ☢️ Radioactive |
Half Life | |
Spin | 0 |
Quadrupole Moment | 0
|
Discovery Year | 2009 |
Parity | + |
Decay Mode | Intensity |
---|---|
β− (β− decay) | |
β− n (β−-delayed neutron emission) | |
2n (2-neutron emission) |
Mass Number | 53 |
---|---|
Neutron Number | 35 |
Relative Atomic Mass | |
G-Factor | |
Abundance | |
Radioactivity | ☢️ Radioactive |
Half Life | |
Spin | 5/2 |
Quadrupole Moment | |
Discovery Year | 2009 |
Parity | - |
Decay Mode | Intensity |
---|---|
β− (β− decay) | |
β− n (β−-delayed neutron emission) | |
2n (2-neutron emission) |
Mass Number | 54 |
---|---|
Neutron Number | 36 |
Relative Atomic Mass | |
G-Factor | 0
|
Abundance | |
Radioactivity | ☢️ Radioactive |
Half Life | |
Spin | 0 |
Quadrupole Moment | 0
|
Discovery Year | 2018 |
Parity | + |
Decay Mode | Intensity |
---|---|
β− (β− decay) | |
β− n (β−-delayed neutron emission) | |
2n (2-neutron emission) |
Argon was suspected to be present in air by Henry Cavendish in 1785. It was not isolated until 1894 by Lord Rayleigh and Sir William Ramsay in Scotland. Argon became the first member of the noble gases to be discovered. In 1957, IUPAC agreed that the symbol should change from A to Ar. From the Greek argos, inactive
Discoverers | Sir William Ramsey, Baron Rayleigh |
---|---|
Discovery Location | Scotland |
Discovery Year | 1894 |
Etymology (Name Origin) | Greek: argos (inactive). |
Pronunciation | AR-gon (English) |
Continuously released into the air by decay of radioactive potassium-40. Pure form is obtained from fractional distillation of liquid air.
Abundance | |
---|---|
Abundance in Earth's crust | |
Natural Abundance (Oceans) | |
Natural Abundance (Human Body) | |
Natural Abundance (Meteor) | |
Natural Abundance (Sun) | 0.007 %
|
Abundance in Universe | 0.02 %
|
1 | s | 0.4925 |
2 | p | 3.9918 |
2 | s | 5.7696 |
3 | p | 11.2359 |
3 | s | 10.2432 |