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Element 17 - Chlorine (Cl) sound

From chloros, or greenish-yellow; discovered 1774. Combining with almost as many elements as fluorine, chlorine is less corrosive but strong enough to be used as a bleach, a disinfectant and a poison gas. Pure chlorine is commonly prepared from ordinary salt (NaCl).

Properties

Atomic Number: 17
Atomic Weight: 35.4527
Electron Configuration (at ground state): 1s22s22p63s23p5
Oxidation States (Bold most stable): -1,+1, +3, +5, +7
Boiling Point (K): 239.18
Melting Point (K): 172.17
Density (at STP -- g/l): 1.696
Atomic Volume (liquid state at boiling point -- cm3/mol) 18.7
Number of stable isotopes: 2
Mass Number (Bold naturally occurring) -- Half-Life -- Disintigration Type: 36 -- 3.01 x 105 years -- beta particle (electron) emission
38 -- 37.2 minutes -- beta particle (electron) emission
Covalent Radius (Å): 0.99
Atomic Radius (Å): 0.97
First Ionization Potential (V): 12.967
Electronegativity (Pauling's): 3.16
Specific Heat Capacity (at 300K -- J g-1 K-1): 0.48
Heat of Vaporization (kJ/mol): 10.20
Heat of Fusion (kJ/mol): 0.26
Thermal Conductivity (at 300K -- W m-1 K-1): 0.0089
Crystal Structure: Orthorhombic
Acid-Base Properties: Very acidic