Helium is a chemical element with symbol He and atomic number 2. It is a colorless, odorless, tasteless, non-toxic, inert, monatomic gas that heads the noble gas group in the periodic table. Its boiling and melting points are the lowest among all the elements.
Three reasons Helium stands out
1
Useful when a very light, unreactive gas is needed.
2
It was discovered in the Sun before it was ever found on Earth.
3
Used to keep scientific equipment extremely cold.
A gas born before the stars
Most helium formed during the universe’s first few minutes, long before planets existed. Its closed electron shell makes it reluctant to react, while its exceptionally low boiling point keeps it liquid in machines that need extreme cold. Once released, its light atoms can eventually escape Earth altogether.
Recognizing Helium in Elementle
If Helium is the mystery element, guesses below atomic number 2 point up and guesses above it point down. Its symbol is He: a green letter matches the same position in that symbol, while a yellow letter belongs in another position.
The family clue turns green for noble gas guesses. Compare Neon (Ne), number 10 and Argon (Ar), number 18: they share the family clue, but their atomic numbers and symbols help you tell them apart.
Values are reference data, not a specification for every temperature, pressure, or allotrope. Unknown properties are left unavailable. Superheavy-element predictions remain uncertain.
The introduction and original editorial story are adapted from Wikipedia contributors via Periodic-Table-JSON. Element descriptions and their adaptations are available under CC BY-SA 3.0. Numerical attributes use the PubChem periodic-table dataset, retrieved September 22, 2026.