Chemical element with symbol He and atomic number 2; rare gas
A colorless, odorless, tasteless, nearly inert noble gas with the symbol He and atomic number 2. It is after hydrogen the second most abundant element in the universe. It is a component of air and is being used for balloon and airship fillings, as well as for deep-sea breathing systems in combination with oxygen.
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.