helium
chemical element with symbol He and atomic number 2; rare gas; noble gas
Press Enter · cited answer in seconds
0 sources
Summary
helium is a chemical element[1]. helium draws 15,853 Wikipedia views per month (chemical element category, ranking #15 of 144).[2]
Key Facts
- Discoverer or inventor: Pierre Janssen[3], Norman Lockyer[4], William Ramsay[5]
- Instance of: atmophile element[6]
- Named after: Helios[7]
- Canonical SMILES: [He][8]
- Element symbol: He[9]
- Chemical formula: He[10]
- Subclass of: nonmetal[11], noble gases[12], s-block[13]
- Part of: period 1[14], noble gases[15]
- Has use: lifting gas[16], coolant[17], component[18], food additive[19]
- Commons category: Helium[20]
- Crystal system: hexagonal crystal system[21]
- Time of discovery or invention: August 18, 1868[22]
- IPA transcription: ˈhiːliəm[23]
- Topic's main category: Category:Helium[24]
- Commons gallery: Helium[25]
- Atomic number: 2[26]
- Electronegativity: 4.5[27]
- Refractive index: 1.000036[28]
- Oxidation state: 0[29]
- Described by source: Armenian Soviet Encyclopedia[30], Great Soviet Encyclopedia (1926–1947)[31], Brockhaus and Efron Encyclopedic Dictionary[32], Small Brockhaus and Efron Encyclopedic Dictionary[33], Otto's encyclopedia[34], Encyclopædia Britannica 11th edition[35], Granat Encyclopedic Dictionary[36]
- Stack Exchange tag: https://astronomy.stackexchange.com/tags/helium[37]
- Has characteristic: colorlessness[38], tastelessness[39], odorlessness[40], diamagnetism[41]
- Different from: Hel[42]
- Density: 0.1785 kilogram per cubic metre[43]
- Specific heat capacity: 5193.0 joule per kilogram kelvin[44]
Why It Matters
helium has Wikipedia articles in 30 language editions, a strong signal of global cultural recognition.[45] helium is known by 37 alternative names across languages and contexts.[46]