Chlorine was discovered by a Swedish scientist, Carl Willam Scheele in 1774.
Name: chlorine
Symbol: Cl
Atomic number: 17
Atomic weight: 35.45
State: gas
Group, period, block: 17, 3, p
Color: pale yellow-green gas
Classification: halogen
Electron configuration: 3s2 3p5
2,8,7
Physical properties
Density @293 K:: 3.214 g/cm-3
Melting point: 171.6 K, -101.5 °C, -150.7 °F
Boiling point: 239.11 K, -34.04 °C, -29.27 °F
Atomic properties
Oxidation states: 7, 6, 5, 4, 3, 2, 1, -1
Electronegativity: 3.16 (Pauling scale)
Ionization energies: 1st: 1251.2 kJ·mol-1
Covalent radius: 102±4 pm
Van der Waals radius: 175 pm
- Cl
Electron Configuration
Isotopes
There are two naturally occurring isotopes of chlorine exist, 35Cl, and 37Cl. 35Cl has a mass of 34.9689 amu with a natural abundance of 75.77%. 37Cl has a mass of 36.9659 amu with a natural abundance of 24.23%. Together they give chlorine an atomic weight of 35.4527 g/mol.