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Element 17 - Chlorine (Cl)
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):
1s
2
2s
2
2p
6
3s
2
3p
5
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 -- cm
3
/mol)
18.7
Number of stable
isotopes
:
2
Mass Number
(Bold naturally occurring) --
Half-Life
--
Disintigration Type
:
36 -- 3.01 x 10
5
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