Helium is an inert, colorless, odorless noble gas with two protons and two electrons and extremely low boiling point.
Properties of Helium | It has very low density, high thermal conductivity and remains liquid at temperatures near absolute zero.
Uses of Helium | Found in natural gas deposits and used for MRI cryogenics, gas chromatography and as a lifting gas in controlled applications.
Isotopes of Helium | Stable isotopes He 3 and He 4 exist; helium is nonreactive and poses asphyxiation risk in confined spaces if it displaces oxygen.