helium
Let an agent explain helium and its properties, relay isotopes, phases, sources and uses from chemistry and physics references, describe liquid and solid helium and the isotopes the registry aliases name, and distinguish helium from hydrogen, from other noble gases and from helium-3 as a separate resource topic.
Research draft, second pass
A second pass drafted this model: the structure a model of this thing needs, and what is known about it in the world. The line under this one says how the second half was obtained - researched against sources, or recalled without web access, in which case nothing here was read anywhere and every claim is a lead to verify. Unreviewed either way.
written by Claude from model knowledge without web access - no source was read, every claim is a lead to verify
Researched by: Claude
Purpose and description
Let an agent explain helium and its properties, relay isotopes, phases, sources and uses from chemistry and physics references, describe liquid and solid helium and the isotopes the registry aliases name, and distinguish helium from hydrogen, from other noble gases and from helium-3 as a separate resource topic.
The chemical element with atomic number 2, symbol He, a colourless, odourless, inert noble gas, the second most abundant element in the universe, discovered in the solar spectrum in 1868, extracted on Earth from natural gas, with stable isotopes helium-4 and helium-3 and short-lived isotopes such as helium-6 and helium-8, and unbound helium-2; liquid helium boils at about 4.2 K and becomes superfluid, and solid helium forms only under pressure, making helium essential for cryogenics, MRI magnets and research.
What it is for: Cryogenics, lifting gas, shielding gas and research.
It can be explain the element; relay isotopes and phases; describe uses and supply; distinguish related substances.
Distinguishing features
Inert noble gas
Lowest boiling point
Superfluidity
Finite terrestrial supply
What it looks like
A colourless gas; liquid helium is a clear, very cold liquid.
Physical character
atomic number: 2 count
boiling point: 4.22 K - helium-4
superfluid transition: 2.17 K - lambda point
discovered: 1868 year - solar spectrum
How it is recognised
Noble gas element 2
Helium-4, helium-3, helium-6, helium-8, helium-2; liquid and solid helium
Hydrogen is element 1 and flammable; neon and argon are heavier noble gases
Related models
is a kind of - in registry terms
is a kind of - in registry terms
is extracted from -
is used in - to cool magnets
In practice
Families and kinds
helium-4
helium-3
unstable isotopes such as helium-6 and helium-8
liquid helium and superfluid helium II
solid helium under pressure
Identifiers
CAS 7440-59-7 helium
atomic number 2
Standards and regulation
Compressed and cryogenic gas safety rules
Strategic helium reserve policies
Failure modes and hazards
Asphyxiation in confined spaces
Cryogenic burns from liquid helium
Supply shortages
Also called
Where this came from
wikidata · CC0 1.0
Also registered as vr.tr.helium
Drafted structure
Bundle to layer to finding to question, as the second pass will find it: 4 bundles · 8 layers · 8 findings · 16 questions.
Understand What helium is.
Science.
Definition
Definition.
Definition
Definition.
- What is helium, and how does it differ from hydrogen and other noble gases? definition
- Is the question about the element, isotopes, phases, uses or supply? boundary
Forms
Isotopes and phases.
Forms
Forms.
- What are helium-4, helium-3, helium-6, helium-8 and helium-2, and liquid and solid helium? definition
- Which entry fits the specific form? action
Physics Physics.
Science.
Superfluid
Superfluidity.
Superfluid
Superfluid.
- How does helium become superfluid, and why does it not freeze at normal pressure? provenance
- Which references are standard? provenance
Origin
Cosmic origin.
Origin
Origin.
- How was helium formed in the Big Bang and stars, and how is it produced by radioactive decay on Earth? provenance
- Which sources are cited? provenance
Uses Uses and supply.
Application.
Uses
Uses.
Uses
Uses.
- How is helium used in MRI, research, welding, leak detection and balloons? provenance
- Which entry fits cryogenics? action
Supply
Supply.
Supply
Supply.
- Where is helium produced, and what supply concerns are reported? provenance
- Which entry fits helium shortage? action
Context Safety and history.
Context.
Safety
Safety.
Safety
Safety.
- What are the hazards of helium gas and liquid helium, as safety agencies describe? provenance
- Which entry fits asphyxiant gas? action
History
History.
History
History.
- How was helium discovered by Janssen and Lockyer and first liquefied by Kamerlingh Onnes? provenance
- Which entry fits the history of cryogenics? action
What the second pass must settle
- Should liquid helium and helium-3 be separate primary entries?
- How should chemistry and physics references be linked?
- The registry entry has merged aliases naming isotopes and phases; should they be split off?