Symbol
He
Atomic Number
2
Atomic Mass
4.002602
Protons
2
Neutrons
2
Electrons
2
Type
Noble Gas
Isotopes
Helium-3, Helium-4
Discovery Year
1868
Discovered By
Pierre Janssen
Group
18
Period
1
Boiling Point
-452°F
Melting Point
-458°F
Electron Configuration
1s²
Density (g/cm³)
0.0001786
Crystal Structure
Cubic
Magnetism
Diamagnetic
Abundance in Earth's Crust
0.00052%
Phase at Room Temperature
Gas