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physical object > natural object > particle > element > column grouped element > inert gas > helium
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helium
(He, 1S0 in ground state)
subjectfact 
heliumhas symbol He2001-09-27 09:28:49.0
has stable isotope helium 3, helium 42001-09-27 09:28:50.0
has lethal intake non-toxic2001-09-27 09:28:49.0
has reserves 3.7 × 109 tonnes in Earth's atmosphere2001-09-27 09:28:50.0
has mineral present in some minerals2001-09-27 09:28:50.0
has neutron scattering length 0.326 × 10-12 cm2001-09-27 09:28:49.0
has electron affinity 0.0 kJ mol-1 from to -2001-09-27 09:28:49.0
has toxic intake non-toxic2001-09-27 09:28:49.0
has mass magnetic susceptibility -5.9 × 10-9 kg-1 m3 for gas2001-09-27 09:28:49.0
has van der Waals radii 120 pm2001-09-27 09:28:49.0
has thermal neutron capture cross section 0.007 barns2001-09-27 09:28:49.0
has longest lived isotope helium 42001-09-27 09:28:50.0
has isotope mass range 3 to 8 except 72001-09-27 09:28:50.0
has number of isotopes 5 including nuclear isomers2001-09-27 09:28:50.0
has pronunciation heel-iuhm2001-09-27 09:28:50.0
has name origin helios = sun from Greek2001-09-27 09:28:50.0
has discovery location England2001-09-27 09:28:50.0
has abundance 6.31 × 1010 in Sun relative to H = 1 × 10122001-09-27 09:28:50.0
has abundance 0.008 p.p.m. in Earth's crust2001-09-27 09:28:50.0
has abundance 5.2 p.p.m. by volume in Earth's atmosphere2001-09-27 09:28:50.0
has abundance 4 × 10-6 p.p.m. in seawater2001-09-27 09:28:50.0
has specimen small pressurized canisters. Safe.2001-09-27 09:28:50.0
has world production 4500 tonnes year-12001-09-27 09:28:50.0
has chief source natural gas which may contain up to 7% helium2001-09-27 09:28:50.0
has mass absorption coefficient 0.383 cm2 g-1 for CuKα X-ray diffraction2001-09-27 09:28:49.0
has mass absorption coefficient 0.207 cm2 g-1 for MoKα X-ray diffraction2001-09-27 09:28:49.0
has space group P63/mmc for α-He at 1.15 K, 6.69 MPa2001-09-27 09:28:49.0
has space group Fm3m for β-He at 16K, 127 MPa2001-09-27 09:28:49.0
has space group Im3m for γ-He at 1.73 K, 2.94 MPa2001-09-27 09:28:49.0
has crystal cell dimension a = 353.1, c = 569.3 pm for α-He at 1.15 K, 6.69 MPa2001-09-27 09:28:49.0
has crystal cell dimension a = 424.0 pm for β-He at 16K, 127 MPa2001-09-27 09:28:49.0
has crystal cell dimension a = 411 pm for γ-He at 1.73 K, 2.94 MPa2001-09-27 09:28:49.0
has crystal type h.c.p. for α-He at 1.15 K, 6.69 MPa2001-09-27 09:28:49.0
has crystal type f.c.c. for β-He at 16K, 127 MPa2001-09-27 09:28:49.0
has crystal type b.c.c. for γ-He at 1.73 K, 2.94 MPa2001-09-27 09:28:49.0
has atomic emission line 388.865 nm for He I2001-09-27 09:28:49.0
has atomic emission line 587.562 nm for He I2001-09-27 09:28:49.0
has atomic emission line 1083.025 nm for He I2001-09-27 09:28:49.0
has atomic emission line 1083.034 nm for He I (strong)2001-09-27 09:28:49.0
has atomic emission line 1868.534 nm for He I2001-09-27 09:28:49.0
has atomic emission line 2058.130 nm for He I2001-09-27 09:28:49.0
has term symbol 1S0 in ground state2001-09-27 09:28:49.0
has electron configuration 1s2 = [He] in ground state2001-09-27 09:28:49.0
has mass of element in person very small for a 70 kg average person2001-09-27 09:28:49.0
has daily dietary intake very low2001-09-27 09:28:49.0
has level in humans traces2001-09-27 09:28:49.0
has hazard harmless but could asphyxiate if it excludes oxygen from the lungs2001-09-27 09:28:49.0
has biological role none2001-09-27 09:28:49.0
has thermal conductivity 0.152 W m-1 K-1 at 300 K2001-09-27 09:28:49.0
has molar volume 32.07 cm3 at 4 K2001-09-27 09:28:49.0
has heat capacity 20.786 J K-1 mol-1 for gas at constant pressure 0.1 MPa at 298.15 K2001-09-27 09:28:49.0
has heat of vaporization 0.082 kJ mol-12001-09-27 09:28:49.0
has heat of fusion 0.021 kJ mol-12001-09-27 09:28:49.0
has boiling point 4.216 K2001-09-27 09:28:49.0
has melting point 0.95 K under pressure2001-09-27 09:28:49.0
has relative atomic mass 4.005602 in units of 12C = 12.0002001-09-27 09:28:49.0
has atomic radii 128 pm2001-09-27 09:28:49.0
has number of protons 22001-09-27 09:28:49.0
has registry number 7440-59-7 for Chemical Abstracts System databasehas source: Chemical Abstracts System, has URL: http://info.cas.org, 2001-09-27 09:28:49.0
has density 124.8 kg m-3 for liquid at 4.216 K boiling point2001-09-27 09:28:49.0
has density 0.1785 kg m-3 for gas at 273 K2001-09-27 09:28:49.0
has synthesis mechanism2001-09-27 09:28:50.0
has ocean oxidation state 02001-09-27 09:28:27.0
has atomic number 22001-09-27 09:28:49.0
reacts with nothing2001-09-27 09:28:49.0
has discovery date 18682001-09-27 09:28:50.0
has discoverer Norman Lockyer and Edward Frankland2001-09-27 09:28:50.0
has uses deep-sea diving, weather baloons, low temperature research2001-09-27 09:28:49.0
has image 2001-09-27 09:28:32.0
has definition Colourless, odorless gas obtained mainly from gas wells. Element which, after hydrogen, is the second lightest and second most abundant in the Universe. Its atom comprises two protons and two electrons. The nucleus of helium 4 is sometimes called an alpha particle. Helium is the product of the nuclear fusion of hydrogen in most stars, but this does not explain the overall helium abundance. Most of it was produced by the big bang, with main-sequence stars making an additional contribution.has source: Abbot, D. 1984 Astronomers, Peter Bedrick Books, New YorkCroswell, K. 1995 The Alchemy of the Heavens, Anchor Books, 2001-09-27 09:28:49.0
has definition2001-09-27 09:28:49.0
is a kind of light element2001-09-27 09:28:19.0
is a kind of inert gas2001-09-27 09:28:24.0
is a kind of unclassified oceanic element2001-09-27 09:28:27.0
has critical pressure 229 kPa2001-09-27 09:28:49.0
has critical temperature 5.25 K2001-09-27 09:28:49.0
unclassified oceanic elementhas ocean residence time unknown2001-09-27 09:28:26.0
has ocean concentration unknown2001-09-27 09:28:26.0
inert gashas group 182001-09-27 09:28:25.0
has synonym group VIII element2001-09-27 09:28:25.0
has synonym noble gas2001-09-27 09:28:25.0
elementis a part of Universe2001-09-27 09:32:17.0
oceanic elementhas occurrence ocean2001-09-27 09:28:26.0
atmophile elementhas occurrence atmosphere of a planet or asteroid2001-09-27 09:28:26.0
gaseous elementhas state gas at standard temperature and pressure2001-09-27 09:28:25.0
particleobeys uncertainty principle2001-09-27 09:28:02.0
has frequency inversely proportional to the wavelength2001-09-27 09:28:02.0
has wavelength inversely proportional to its momentum2001-09-27 09:28:02.0
has charge2001-09-27 09:28:01.0
has mass2001-09-27 09:28:02.0
physical objecthas location or center of gravity2001-09-27 09:27:27.0
has angular momentum2001-09-27 09:27:27.0
has velocity2001-09-27 09:27:27.0
has momentum2001-09-27 09:27:27.0
has temperature2001-09-27 09:27:27.0
has volume2001-09-27 09:27:27.0
has extent2001-09-27 09:27:27.0
has material2001-09-27 09:27:27.0

Kinds of helium :

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