If you want to know where the data comes from for any particular property, then select that property. You'll see graphs for the properties as well. Helium gas is unreactive, colourless, and odourless. Helium is available in pressurised tanks.
Elemental helium is a colourless odourless monoatomic gas.
Helium is the second most abundant element in the universe after hydrogen. Emma's first birthday balloon is filled with helium and so rises in air. All rights reserved.