ᱪᱷᱟᱸᱪ:Infobox helium

ᱦᱤᱞᱤᱭᱟᱢ,  ₂He

ᱦᱤᱞᱤᱭᱟᱢ
Pronunciation	/ˈhiːliəm/ ​(HEE-lee-əm)
Appearance	colorless gas, exhibiting a gray, cloudy glow (or reddish-orange if an especially high voltage is used) when placed in an electric field
Standard atomic weight Ar, std(He)	7000400260200000000♠4.002602(2)
ᱦᱤᱞᱤᱭᱟᱢ in the periodic table
Hydrogen Helium Lithium Beryllium Boron Carbon Nitrogen Oxygen Fluorine Neon Sodium Magnesium Aluminium Silicon Phosphorus Sulfur Chlorine Argon Potassium Calcium Scandium Titanium Vanadium Chromium Manganese Iron Cobalt Nickel Copper Zinc Gallium Germanium Arsenic Selenium Bromine Krypton Rubidium Strontium Yttrium Zirconium Niobium Molybdenum Technetium Ruthenium Rhodium Palladium Silver Cadmium Indium Tin Antimony Tellurium Iodine Xenon Caesium Barium Lanthanum Cerium Praseodymium Neodymium Promethium Samarium Europium Gadolinium Terbium Dysprosium Holmium Erbium Thulium Ytterbium Lutetium Hafnium Tantalum Tungsten Rhenium Osmium Iridium Platinum Gold Mercury (element) Thallium Lead Bismuth Polonium Astatine Radon Francium Radium Actinium Thorium Protactinium Uranium Neptunium Plutonium Americium Curium Berkelium Californium Einsteinium Fermium Mendelevium Nobelium Lawrencium Rutherfordium Dubnium Seaborgium Bohrium Hassium Meitnerium Darmstadtium Roentgenium Copernicium Nihonium Flerovium Moscovium Livermorium Tennessine Oganesson – ↑ He ↓ Ne hydrogen ← ᱦᱤᱞᱤᱭᱟᱢ → lithium
Atomic number (Z)	2
Group	group n/a
Period	[[Period {{{period}}} element|period {{{period}}}]]
Block	[[{{{block}}}-block]]
Element category	Noble gas
Electron configuration	1s2
Electrons per shell	2
Physical properties
Phase at STP	gas
Boiling point	4.222 K ​(−268.928 °C, ​−452.070 °F)
Density (at STP)	0.1786 g/L
when liquid (at b.p.)	0.125 g/cm3
Triple point	2.177 K, ​5.043 kPa
Critical point	5.1953 K, 0.22746 MPa
Heat of fusion	0.0138 kJ/mol
Heat of	0.0829 kJ/mol
Molar heat capacity	20.78 J/(mol·K)
pressure (defined by ITS-90) P (Pa) 1 10 100 1 k 10 k 100 k at T (K)     1.23 1.67 2.48 4.21
Atomic properties
Oxidation states	0
Electronegativity	Pauling scale: no data
energies	1st: 2372.3 kJ/mol 2nd: 5250.5 kJ/mol
Covalent radius	28 pm
Van der Waals radius	140 pm
Spectral lines of ᱦᱤᱞᱤᱭᱟᱢ
Other properties
Natural occurrence	primordial
Crystal structure	​hexagonal close-packed (hcp)
Speed of sound	972 m/s
Thermal conductivity	0.1513 W/(m·K)
Magnetic ordering	diamagnetic
Magnetic susceptibility	3005812000000000000♠−1.88×10−6 cm3/mol (298 K)
CAS Number	7440-59-7
History
Naming	after Helios, Greek god of the Sun
Discovery	Norman Lockyer (1868)
First isolation	William Ramsay, Per Teodor Cleve, Abraham Langlet (1895)
Iso­tope Abun­dance Half-life (t1/2) Decay mode Pro­duct

PTHelium

H ← i'box H	iso 2He  infobox  isobox	→ Li i'box Li
Commons  Wikidata:  Wiktionary Indexes in PT: § below · Page

[]  Data sets read by {{Infobox element}}
Name and identifiers
Top image (caption, alt)
Pronunciation
Category (enwiki)
Standard atomic weight
most stable isotope
Natural occurence
Phase at STP
Oxidation states
Spectral lines image
Electron configuration (cmt, ref)
Term symbol * (cmt, ref)
Wikidata *
* Not used in {{Infobox element}} (2019-02-03) See also {{Infobox element/symbol-to--navbox}}

References

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• <ref name = "CIAAW2013" /> for the source Atomic weights of the elements 2013 (from subtemplates used by {{Infobox element}})