Atomic Number 17     Atomic Mass 35.4527      State gas     Color yellow-green

Electronegativity 3.16     Melting Point -100.98°C      Boiling Point -34.6°C

Natural Isotopes  Cl-35 75.77%   Cl-37 24.23%

Abbreviated Electron Configuration [Ne] 3s² 3p⁵

Discovered by Carl William Scheele in 1774.