helium

en-noun

helium (countable and uncountable, plural heliums)

From New Latin helium, from Ancient Greek ἥλιος (hḗlios, “sun”) (because its presence was first theorised in the Sun's atmosphere) with the suffix + -ium. Probably coined by Norman Lockyer. This suffix is unusual, because it is usually used only for metallic elements. It is likely that Lockyer, being an astronomer, was unaware of the usual chemical conventions.

It was an enormous balloon filled with helium, that elemental gas forged from hydrogen in the nuclear furnace of the stars.

1997, Ian McEwan, Enduring Love, Vintage (1998), page 3:

(uncountable) The second lightest chemical element (symbol He) with an atomic number of 2 and atomic weight of 4.002602, a colorless, odorless and inert noble gas.


neon

neon (countable and uncountable, plural neons)

Borrowed from Ancient Greek νέον (néon), neuter of νέος (néos, “new”), from earlier *νέϝος (*néwos), from Proto-Hellenic *newos, from Proto-Indo-European *néwos.

(uncountable) The chemical element (symbol Ne) with an atomic number of 10. The second of the noble gases, it is a colourless, odorless inert gas.


argon

argon (countable and uncountable, plural argons)

From Ancient Greek ἀργόν (argón), neuter of ἀργός (argós, “idle, lazy”), because of its inertness.

The chemical element (symbol Ar) with an atomic number of 18. The third most abundant gas in the Earth's atmosphere, it is a colourless, odourless, inert noble gas.


krypton

krypton (countable and uncountable, plural kryptons)

Neuter form of Ancient Greek κρυπτός (kruptós, “hidden”).

uder

(uncountable) The chemical element (symbol Kr) with an atomic number of 36. It is a colourless, odourless noble gas that only reacts with fluorine. It is one of the rarest gases in the Earth's atmosphere.


xenon

en-noun

xenon (usually uncountable, plural xenons)

From Ancient Greek ξένον (xénon), neuter of ξένος (xénos, “foreign, strange”).

The chemical element (symbol Xe) with an atomic number of 54. It is a colorless, odorless, unreactive noble gas, used notably in camera flash technology.


radon

Contraction of radium emanation, since the element appears in the radioactive decay of radium.

The chemical element (symbol Rn, formerly Ro) with atomic number 86. It is an odorless, colorless, chemically inert but radioactive noble gas.


noble gas

(chemistry) Any of the elements of group 18 of the periodic table, being monatomic and (with very limited exceptions) inert.

edelgas

element of group 18 of the periodic table


alpha particle

LL-Q1860 (eng)-Flame, not lame-alpha particle.wav

(physics) A doubly positively charged nucleus of a helium-4 atom (consisting of two protons and two neutrons), emitted as a consequence of radioactivity; α-particle


helion

(physics) A helium ion, the nucleus of a helium-3 atom. Formula: ³He⁺² ; Symbol: h


helium speech

Speech whose timbre (but not pitch) has been affected by the inhalation of helium, due to the difference in the speed of sound in that gas, compared with air.


perxenate

(inorganic chemistry) The anion XeO₆⁴⁻ formally derived from perxenic acid; any salt containing this anion.


liquid helium

(physics) The liquified form of helium that does not solidify even at absolute zero; it shows unusual properties, such as superfluidity, due to quantum effects.


heliox

(medicine, underwater diving) A mixture of helium and oxygen used as a breathing gas.


heliair

(underwater diving) A mixture of helium, nitrogen and oxygen, used as a breathing gas instead of normal air.


helium dating

(archaeology) a method of determining the age of rock that depends on the production of helium during the decay of various radioactive isotopes of uranium and thorium.


xenon difluoride

(inorganic chemistry) a crystalline substance, XeF₂, used as a fluorinating agent and oxidizing agent in various surface modification processes, and as an etching agent in semiconductor production


helium burning

(physics, astronomy) the nucleosynthesis process, in stars with temperatures over 10⁸K, in which helium is converted to carbon and then to oxygen, neon and magnesium

Heliumbrennen

process, in which helium is converted to carbon


helium star

(astronomy) A star which has lost most or all of its hydrogen, leaving just a core of helium.


helium variable

helium variable (plural helium variables)

(astronomy) A star in which the strength of the helium absorption lines vary periodically; at times appearing to be a helium star.


parahelium

(physics) The form of the helium atom in which the spins of the two electrons form a singlet state (a state with zero total spin)


neon lamp

A small gas discharge lamp containing neon gas, sometimes with other noble gases to add colour.


neon sign

Just listen to the music and the traffic of the city / Linger on the sidewalk where the neon signs are pretty

1979, “Downtown”, performed by The B-52's:

An illuminated sign constructed from fluorescent lights in the form of bent glass tubes; the different colours being obtained by adding different noble gases to the neon.

霓虹燈招牌 /霓虹灯招牌

an illuminated sign constructed from fluorescent lights


neon light

neon light (countable and uncountable, plural neon lights)


neon lighting

neon lighting (usually uncountable, plural neon lightings)


harmonium

Borrowed from French harmonium, a term coined by French inventor Alexandre Debain in 1840.


xenon flash lamp

en-noun

xenon flash lamp (plural xenon flash lamps)

A lamp that produces a very short, but very intense, flash of white light; used in photography and in photocoagulation

xenon villanólámpa

a lamp that produces a short, intense flash of light


superfluid

LL-Q1860 (eng)-Flame, not lame-superfluid.wav

(physics) A substance, such as liquid helium, that exhibits superfluidity.


alpha emission

(physics) A form of radioactivity in which alpha particles are emitted from the nucleus of an atom

alfasäteily

emission of alpha particles from the nucleus of an atom


potassium-argon dating

potassium-argon dating (usually uncountable, plural potassium-argon datings)

(geology) A method of estimating the age of igneous rocks or of archaeological objects by measuring the amount of argon that has built up through the radioactive decay of potassium.


With its magnetic field drastically weakened and much of its atmosphere lost, what remains intact of H-047c's surface is vulnerable to cosmic radiation. This has rendered the soil unable to support life, though it is a potential source of valuable helium-3.

2017, BioWare, Mass Effect: Andromeda (science fiction), Redwood City: Electronic Arts, →OCLC, PC, scene: H-047c Codex entry:

(physics) The rare isotope of helium, ³₂He, that has a single neutron.


(physics) The normal isotope of helium, ⁴₂He, that has two neutrons


(physics) The major stable isotope of neon, ²⁰₁₀Ne, having ten protons and ten neutrons; it amounts to over 90% of the element in nature


(physics) A rare stable isotope of neon, ²¹₁₀Ne, having ten protons and eleven neutrons; it amounts to less than 0.3% of the element in nature


(physics) A minor stable isotope of neon, ²²₁₀Ne, having ten protons and twelve neutrons; it amounts to about 9% of the element in nature


(physics) A rare stable isotope of argon, ³⁶₁₈Ar, having eighteen protons and eighteen neutrons; it amounts to about 0.3% of the element in nature


(physics) A rare stable isotope of argon, ³⁸₁₈Ar, having eighteen protons and twenty neutrons; it amounts to about 0.06% of the element in nature


(physics) The major stable isotope of argon, ⁴⁰₁₈Ar, having eighteen protons and twenty-two neutrons; it amounts to about 99.6% of the element in nature


xenon hexafluoroplatinate

(inorganic chemistry) The first compound of an inert gas to be prepared; it seems to have the formula XePtF₆, but its structure is ambiguous, and may be a mixture.


alpha decay

(physics) radioactive decay by emitting an alpha particle.


xenate

(inorganic chemistry) The oxyanion of xenon HXeO₄⁻.


diproton

A hypothetical particle consisting of two protons and no neutrons; a helium-2 nucleus. Presumably an intermediate step in the fusion of hydrogen into helium.


organoxenon

(organic chemistry) Describing any organic compound containing a carbon to xenon bond.


antihelium

antihelium (countable and uncountable, plural antiheliums)

In 1970, a more complex antinucleus, antihelium-3 (iHe), was discovered in the USSR.

1987, K. N. Mukhin, Experimental Nuclear Physics: Elementary particle physics, page 134:

In principle the energy should have been enough for the production of even heavier antinuclei. However, the probability for production of heavier masses is very tiny, and antihelium-3 is still the heaviest known antielement.

1994, Sven Kullander, Kullander Sven, Börje Larsson, Out of Sight!: From Quarks to Living Cells, →ISBN, page 218:

After several launches of their balloon, the scientists registered more than 40 million nuclei of helium in the cosmic rays, but not a single nucleon of antihelium.

2018, Borissov Guennadi, Story Of Antimatter, The: Matter's Vanished Twin, →ISBN, page 91:


Hooke's atom

The harmonic potential used to describe the electron-nucleus interaction is a consequence of Hooke's law.

(quantum mechanics) An artificial helium-like atom where the Coulombic electron-nucleus interaction potential is replaced by a harmonic potential.


trimix

trimix (countable and uncountable, plural trimixes)

(underwater diving) A mixture of helium, nitrogen, and oxygen used in deep diving as a breathing gas instead of air.


tetraxenon

(inorganic chemistry, especially in combination) Four xenon atoms in a molecule


tetraxenonogold

(inorganic chemistry) The cation AuXe₄²⁺


helium hydride

(inorganic chemistry) Ellipsis of helium hydride cation. The unstable binary cation HeH⁺ present in interstellar space. It is the strongest acid, reactive with every chemical species except positive ions, including electrons.


argon fluorohydride

(inorganic chemistry) The unstable compound, HArF, formed by reacting argon with hydrogen fluoride


krypton difluoride

(inorganic chemistry) A binary compound of krypton and fluorine


perxenic

(inorganic chemistry) Relating to perxenic acid or its derivatives.


perxenic acid

(inorganic chemistry) The acid H₄XeO₆, presumed to be formed by solution of xenon tetroxide in water, but known only as its salts, the perxenates


xenic

(inorganic chemistry) Relating to xenic acid.


xenic acid

(inorganic chemistry) The powerful oxidizing agent H₂XeO₄ formed by the dissolution of xenon trioxide in water


LHe

Abbreviation of liquid helium (a liquid composed of the liquid phase of molecular (atomic) helium (He))


kryptonate

Either from krypton + -ate (forms nouns with perfect meaning, as if: "kryptonated") or a back-formation of kryptonation on the basis of the same suffix. Compare fermentate.

af

(inorganic chemistry) The material formed by such kryptonation.


kryptonation

The infusion of a solid with krypton gas


(physics) A radioactive isotope, ⁸⁵₃₆Kr, having thirty-six protons and forty-nine neutrons


dihelium

(chemistry, especially in combination) Two helium atoms in a molecule.


dixenon

(chemistry, especially in combination) Two xenon atoms in a molecule.


neide

(inorganic chemistry) A binary compound of neon and another element.


oganesson

/oʊɡəˈnɛsɒn/

From Oganessian + -on. Promulgated in June 2016 by IUPAC based on recommendations of the Joint Institute for Nuclear Research and Lawrence Livermore National Laboratory to honor Russian-Armenian physicist Yuri Oganessian (born 1933) who researched superheavy elements. Suffix -on, rather than -ium, is because it is a noble gas (like neon or argon).

SINGAPORE - The four new elements announced in December last year have received their new names: Nihonium (Nh), moscouvium (Mc), tennessine (Ts) and oganesson (Og).

2016 June 9, “Meet the periodic table's 4 new elements: Nihonium, moscouvium, tennessine and oganesson”, in The Straits Times:

In January 2016 the International Union of Pure and Applied Chemistry (IUPAC) announced the discovery of four new elements, so completing the seventh row of the periodic table. They have since been named as nihonium, Nh, muscovium^([sic]), Mc, tennessine, Ts, and organesson^([sic]), Og. The procedures for naming new elements are clearly laid out by IUPAC.

2018, Mark Weller, Tina Overton, Fraser Armstrong, Jonathan Rourke, chapter 1, in Inorganic Chemistry, Oxford University Press, →ISBN, page 21:

Researchers carefully choose the makeup of the beam and the target in hopes of producing a designer atom of the element desired. That’s how the four newest elements were created: nihonium (element 113), moscovium (115), tennessine (117) and oganesson (118) (SN Online: 11/30/16).

2019 February 27, Emily Conover, “Extreme elements push the boundaries of the periodic table”, in Science News:

post-transition metal
post-transition metal

The chemical element (Symbol Og) with atomic number 118. It is the heaviest known element. Highly radioactive, it does not occur naturally. Originally expected to be a noble gas, it is now predicted to be a reactive metallic solid, and a semiconductor or a post-transition metal.


argonium

Our results demonstrate the suitability of argonium as a tracer of the almost purely atomic, diffuse ISM in high-redshift sources.

2015, Holger S.P. Müller, Sébastien Muller, Peter Schilke, Edwin A. Bergin, John H. Black, Maryvonne Gerin, Dariusz C. Lis, David A. Neufeld, Sümeyye Suri, “Detection of extragalactic argonium, ArH⁺, toward PKS~1830-211”, in arXiv:

A cation (ArH⁺) formed by protonation of an argon atom


hyperhelium

Using the coalescence model based on the phase-space distributions of protons, neutrons, Lambdas and their antiparticles from a multiphase transport (AMPT) model, we study the production of deuteron, triton, helium 3, hypertriton, hyperhelium 3 and their antinuclei in Pb+Pb collisions at #92;sqrt#123;s#95;#123;NN

2015, Lilin Zhu, Che Ming Ko, Xuejiao Yin, “Light (anti-)nuclei production and flow in relativistic heavy-ion collisions”, in arXiv:

(physics) A nuclear complex formed from a helium nucleus by replacement of a neutron by a hyperon


xenonate

(inorganic chemistry) The oxyanion of xenon XeO₄²⁻.


helide

(inorganic chemistry) A binary compound of helium and another element.


argide

(inorganic chemistry) A binary compound of argon and another element.


helonium

(inorganic chemistry) Synonym of helium hydride


argonide

Presence of nitrides, argonides, arsenides, and iodides in the crystalline rocks

2017, Kathleen F. Edwards, Joel F. Liebman, No Nobel for Noble Gases - Some Guesses Why:

argon, argonide

2005, IUPAC, Nomenclature of Inorganic Chemistry:

The possibility of obtaining solid pseudosolutions of inert gases such as titanium argonide, scandium heliumide, etc., has been demonstrated

1989, M.D. Gabovich, N.N. Semashko, N.V. Pleshivtsev, Ion and atomic beams for controlled fusion and technology:

Microwave resonance spectrometry, laser induced fluorescence and mass spectrometry have identified and obtained information on the structure and energy levels of such unlikely species as KAr, HeI2, Co2C12He and aniline argonide

1985, J.B Fenn, Where are we going with molecular beams?:

1899, The American Journal of Science, Volume 158, "On Argon And Its Combinations"
The results obtained lead the author to suspect the existence of metallic argonides in those minerals which evolve argon under the action of acids, or even of hydrogen argonide.


neonide

Much more recently neonides (and kryptonides and xenonides) were posited.

neon, neonide


kryptide

kryptides (plural)
kryptonide (alternative)

It can be shown that the hypothetical chlorine kryptide would be endothermic to the extent of 165,000 calories

1933, George Glockler, Charles P. Roe, Donald L. Fuller, Complex Formation due to Polarization. I. The System Krypton and Hydrogen Chloride:

The binding of the xenide is expected to be higher than the argide or kryptide because the polarizability is larger and therefore the magnitude of charge induced dipole interaction as well.

1994, R.L. Asher, Experimental and Theoretical Investigation and Characterization of Small Molecular Ions:

(inorganic chemistry) A binary compound of krypton


xenide

1994, RL Asher, "Experimental and Theoretical Investigation and Characterization of Small Molecular Ions'
The binding of the xenide is expected to be higher than the argide or kryptide because the polarizability is larger and therefore the magnitude of charge induced dipole interaction as well.

Crystal Structures and Electronic Properties of Cesium Xenides at High Pressures

2019, Xiao Z. Yan, Yang M. Chen, Hua Y. Geng, Prediction of the Reactivity of Argon with Xenon under High Pressures:

(inorganic chemistry) A binary compound of xenon


xenonide

xenon, xenonide


kryptonide

kryptonides (plural)
kryptide (alternative)

krypton, kryptonide


helium descrambler

en-noun

helium descrambler (plural helium descramblers)

(technical diving, saturation diving, underwater diving) An electronic device that lowers the pitch of speech, to compensate for the high-pitched speech of someone breathing in a helium atmosphere mixture (e.g. heliox or heliair), so as to be understandable to other people.


helionium

* (helion-antihelion pair): helium + -onium

Any atomic system containing a helium nucleus and an antihelium nucleus.


antihelion

The antiparticle of a helion, consisting of two antiprotons and one antineutron.


xenon tetroxide

(inorganic chemistry) A chemical compound, XeO₄.


antiprotonic helium

A form of helium where one of the electrons is replaced by an antiproton.