Chlorine (Cl) is a chemical element belonging to the category Halogen, with atomic number 17 and atomic mass 35.4500 u. This sheet describes its fundamental properties, periodic position and physical characteristics.
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Astronomy · Chemical element
Chlorine
ELH
Identity
Name: Chlorine
Symbol: Cl
Atomic number: 17
Atomic mass: 35.4500 u
Position in the periodic table
Group: 17
Period: 3
Category: Halogen
Physico-chemical properties
Standard state: Gas
Melting point: -101°C
Density (gas at 0°C and 1 atm): 0.0032 g/cm³
Electron configuration: [Ne] 3s² 3p⁵
Scientific description
Chlorine is a chemical element with symbol Cl and atomic number 17.
It belongs to the category of halogens and occupies group 17 and period 3.
Its standard atomic mass is 35.4500 u.