Helium
From Wikiversity
Helium (He) is the second element of the periodic table. It exists almost solely as a gas, and is very unreactive. It belongs to a group of elements on the periodic table known as noble gases.
[edit] Physical Constants
Molecular Weight = 4.0026 g·mol-1
Melting Point = -272°C
Boiling Point = -268.94°C
Density = 0.138 g·mL-1[1]
