Chlorine

Name: Chlorine
Symbol: Cl
Atomic Number: 17
Atomic Mass: 35.4527 amu
Melting Point: -100.98 °C (172.17 K, -149.764 °F)
Boiling Point: -34.6 °C (238.55 K, -30.279997 °F)
Number of Protons/Electrons: 17
Number of Neutrons: 18
Classification: Halogen
Structure: Orthorhombic
Density @ 293 K: 3.214 g/cm3
Color: green

Date of Discovery: 1774
Discoverer: Carl Wilhelm Scheele
Name Origin: From the Greek word khlôros (green)
Uses: Water purification, bleaches
Obtained From: Salt