imported>DePiep: /* top */rm unused parameter (read from dataset), removed: |category comment = , |group = 18 , |period = 1 , |block = s

2021-05-31T16:45:22Z

top: rm unused parameter (read from dataset), removed: |category comment = , |group = 18 , |period = 1 , |block = s

New page

{{Infobox element
|name = helium
|number = 2
|symbol = He
|abundance =
|abundance in earth's crust =
|abundance in oceans =
|abundance in solar system =
|left = [[hydrogen]]
|right = [[lithium]]
|above = –
|below = [[neon|Ne]]
|appearance = colorless gas, exhibiting a gray, cloudy glow (or reddish-orange if an especially high voltage is used) when placed in an electric field
|image name = Helium discharge tube.jpg
|image alt = A clear tube with a red light emanating from it
|electrons per shell = 2
|phase =
|phase comment =
|density gplstp = 0.1786
|density gpcm3nrt =
|density gpcm3bp = 0.125
|density gpcm3mp = 0.145
|melting point K = 0.95
|melting point C = −272.20
|melting point F = −457.96
|melting point comment = (at 2.5 MPa)
|boiling point K = 4.222
|boiling point C = −268.928
|boiling point F = −452.070
|triple point K = 2.177
|triple point kPa = 5.043
|critical point K = 5.1953
|critical point MPa = 0.22746
|heat fusion = 0.0138
|heat vaporization = 0.0829
|heat capacity = 20.78
|heat capacity ref = <ref>Shuen-Chen Hwang, Robert D. Lein, Daniel A. Morgan (2005). "Noble Gases". ''Kirk Othmer Encyclopedia of Chemical Technology''. Wiley. pp. 343–383. [[doi:10.1002/0471238961.0701190508230114.a01]].</ref>
|vapor pressure 1 =  
|vapor pressure 10 =  
|vapor pressure 100 = 1.23
|vapor pressure 1 k = 1.67
|vapor pressure 10 k = 2.48
|vapor pressure 100 k = 4.21
|vapor pressure comment = (defined by [[International Temperature Scale of 1990|ITS-90]])
|crystal structure = hexagonal close-packed
|electronegativity = no data
|number of ionization energies = 2
|ionization energy 1 = 2372.3
|ionization energy 2 = 5250.5
|ionization energy 3 =
|atomic radius =
|atomic radius calculated =
|covalent radius = 28
|Van der Waals radius = 140
|magnetic ordering = [[diamagnetic]]
|magnetic ordering ref = <ref>[http://www-d0.fnal.gov/hardware/cal/lvps_info/engineering/elementmagn.pdf Magnetic susceptibility of the elements and inorganic compounds], in Handbook of Chemistry and Physics 81st edition, CRC press.</ref>
|electrical resistivity =
|electrical resistivity at 0 =
|electrical resistivity at 20 =
|thermal conductivity = 0.1513
|thermal conductivity 2 =
|thermal diffusivity =
|thermal expansion =
|thermal expansion at 25 =
|speed of sound = 972
|speed of sound rod at 20 =
|speed of sound rod at r.t. =
|magnetic susceptibility = {{val|−1.88|e=−6}}
|magnetic susceptibility ref =  (298 K)<ref>{{cite book |title=CRC, Handbook of Chemistry and Physics|last=Weast|first=Robert|publisher=Chemical Rubber Company Publishing|year=1984|isbn=0-8493-0464-4|location=Boca Raton, Florida|pages=E110}}</ref>
|Young's modulus =
|Shear modulus =
|Bulk modulus =
|Poisson ratio =
|Mohs hardness =
|Vickers hardness =
|Brinell hardness =
|CAS number = 7440-59-7
|isotopes =
{{Infobox element/isotopes stable | mn = 3 | sym = He | na = 0.0002% | n = 1 | link = Helium-3 |firstlinks = yes}}
{{Infobox element/isotopes stable | mn = 4 | sym = He | na = 99.9998% | n = 2 | link = Helium-4 |firstlinks = no}}
|isotopes comment =
|naming = after [[Helios]], Greek [[List of Greek mythological figures|god]] of the Sun
|predicted by =
|prediction date =
|discovered by = [[Pierre Janssen]], [[Norman Lockyer]]
|discovery date = 1868
|first isolation by = [[William Ramsay]], [[Per Teodor Cleve]], [[Abraham Langlet]]
|first isolation date = 1895
|QID = Q560
}}<noinclude>
{{Infobox element/element navigation|symbol = He}}
{{Template reference list}}
One of these is a [[WP:REFNAME|named reference]]. It may be cited in the containing article as
*<nowiki><ref name = "CIAAW2013" /</nowiki>> for the source ''Atomic weights of the elements 2013'' (from subtemplates used by {{tl|Infobox element}})
{{Documentation|1 = Template:Infobox element/doc}}
+
[[Category:Templates that generate named references]]
</noinclude>

Template:Infobox helium - Revision history

imported>DePiep: /* top */rm unused parameter (read from dataset), removed: |category comment = , |group = 18 , |period = 1 , |block = s