Symbol
Cl
Atomic Number
17
Atomic Mass
35.45
Protons
17
Neutrons
18
Electrons
17
Type
Halogen
Isotopes
Chlorine-35, Chlorine-37
Discovery Year
1774
Discovered By
Carl Wilhelm Scheele
Group
17
Period
3
Boiling Point
-29°F
Melting Point
-150°F
Electron Configuration
[Ne] 3s² 3p⁵
Density (g/cm³)
0.003214
Crystal Structure
Orthorhombic
Magnetism
Diamagnetic
Abundance in Earth's Crust
0.017%
Phase at Room Temperature
Gas