Symbol: Cl
Atomic Number: 17
Atomic Weight: 35.4527
Element Classification: Halogen
Discovered By: Carl Wilhelm Scheele
Discovery Date: 1774 (Sweden)
Name Origin: Greek: chloros (greenish yellow).
Density (g/cc): 1.56 (@ -33.6°C)
Melting Point (K): 172.2
Boiling Point (K): 238.6
Appearance: Greenish-yellow, disagreeable gas
Atomic Radius (pm): n/a
Atomic Volume (cc/mol): 18.7
Covalent Radius (pm): 99
Ionic Radius: 27 (+7e) 181 (-1e)
Specific Heat (@20°C J/g mol): 0.477 (Cl-Cl)
Fusion Heat (kJ/mol): 6.41 (Cl-Cl)
Evaporation Heat (kJ/mol): 20.41 (Cl-Cl)
Thermal Conductivity (@25°C W/m K):
Debye Temperature (K): n/a
Pauling Negativity Number: 3.16
First Ionizing Energy (kJ/mol): 1254.9
Oxidation States: 7, 5, 3, 1, -1
Electronic Configuration: [Ne] 3s² 3p⁵
Lattice Structure: Orthorhombic (ORC)
Lattice Constant (Å): 6.240
Lattice C/A Ratio: n/a