helium
Sign in to saveHelium (from ) is a chemical element; it has symbol He and atomic number 2. It is a colorless, odorless, non-toxic, inert, monatomic gas and the first in the noble gas group in the periodic table. Its boiling point is the lowest among all the elements, and it does not have a melting point at standard pressures. It is the second-lightest and second-most abundant element in the observable universe, after hydrogen. It is present at about 24% of the total elemental mass, which is more than 12 times the mass of all the heavier elements combined. Its abundance is similar to this in both the Sun and
AI overview
Helium is a lightweight, colorless gas that is chemically inert (meaning it doesn't react with other elements) and the second-most abundant element in the universe after hydrogen. It matters because of its unique properties—it has the lowest boiling point of any element and remains useful in various scientific and industrial applications due to its inert nature.
AI-generated from the Wikipedia summary — may contain errors.
Chemical data
- Formula
- He
- Molecular weight
- 4.0026 g/mol
- IUPAC name
- helium
via PubChem
Wikidata facts
- Instance of
- atmophile element
- Subclass of
- s-block
- Part of
- noble gases
- Named after
- Helios
- Mass
- +4.002602
- Image
- Helium discharge tube.jpg
Show 10 more facts
Article
36 sectionsContents
- History
- Scientific discoveries
- Extraction and use
- Characteristics
- Atom
- In quantum mechanics
- Related stability of the helium-4 nucleus and electron shell
- Gas and plasma phases
- Liquid phase
- Helium I
- Helium II
- Solid phases
- Isotopes
- Properties
- Compounds
- Occurrence and production
- Natural abundance
- Modern extraction and distribution
- Conservation advocates
- Applications
- Controlled atmospheres
- Gas tungsten arc welding
- Minor uses
- Industrial leak detection
- Flight
- Minor commercial and recreational uses
- Scientific uses
- Medical uses
- Inhalation and safety
- Effects
- Hazards
- See also
- Notes
- References
- Bibliography
- External links
{{Redirect|2He|the isotope of helium with two nucleons ({{chem2|^{2}He}})|Helium-2}}
Helium (from ) is a chemical element; it has symbol He and atomic number 2. It is a colorless, odorless, non-toxic, inert, monatomic gas and the first in the noble gas group in the periodic table. Its boiling point is the lowest among all the elements, and it does not have a melting point at standard pressures. It is the second-lightest and second-most abundant element in the observable universe, after hydrogen. It is present at about 24% of the total elemental mass, which is more than 12 times the mass of all the heavier elements combined. Its abundance is similar to this in both the Sun and Jupiter, because of the very high nuclear binding energy (per nucleon) of helium-4 with respect to the next three elements after helium. This helium-4 binding energy also accounts for why it is a product of both nuclear fusion and radioactive decay. The most common isotope of helium in the universe is helium-4, the vast majority of which was formed during the Big Bang. Large amounts of new helium are created by nuclear fusion of hydrogen in stars.