Chlorine
17
sulfur ← chlorine → argon
F
↑
Cl
↓
Br
Periodic table
General
Name, symbol,
number
chlorine, Cl, 17
Element category
Halogen
Group, period,
block
17, 3, p
Appearance
pale green gas
Standard atomic
weight
35.453(2) g·mol−1
Electron
configuration
[Ne] 3s2 3p5
Electrons per shell 2, 8, 7 (Image)
Physical properties
Phase
gas
Density
(0 °C, 101.325 kPa)
3.2 g/L
Melting point
171.6 K
(-101.5 °C, -150.7 °F)
Boiling point
239.11 K
(-34.4 °C, -29.27 °F)
Critical point
416.9 K, 7.991 MPa
Heat of fusion
(Cl2) 6.406 kJ·mol−1
Heat of
vaporization
(Cl2) 20.41 kJ·mol−1
Specific heat
capacity
(25 °C) (Cl2)
33.949 J·mol−1·K−1
Vapor pressure
P/Pa
1
10
100 1 k 10 k 100 k
at T/K 128 139 153 170 197 239
Atomic properties
Crystal structure
orthorhombic
Oxidation states
-1, +1, +3, +5, +7
(strongly acidic oxide)
Electronegativity
3.16 (Pauling scale)
1st: 1251.2 kJ·mol−1
2nd: 2298 kJ·mol−1
Ionization energies
(more)
3rd: 3822 kJ·mol−1
Atomic radius
100 pm
Atomic radius
(calc.)
79 pm
Covalent radius
99 pm
Van der Waals
radius
175 pm
Miscellaneous
Magnetic ordering diamagnetic[1]
Electrical
resistivity
(20 °C) > 10 Ω·m
Thermal
conductivity
(300 K)
8.9x10-3 W·m−1·K−1
Speed of sound
(gas, 0 °C) 206 m/s
CAS registry
number
7782-50-5
Most stable isotopes
Main article: Isotopes of chlorine
iso
NA
half-life DM DE
(MeV)
DP
35Cl 75.77% 35Cl is stable with 18
neutrons
β-
0.709
36Ar
36Cl syn
3.01×105
y
ε
-
36S
37Cl 24.23% 37Cl is stable with 20
neutrons
References
Chlorine (pronounced /ˈklɔərin/, from the
Greek word ’χλωρóς’ (khlôros, meaning ’pale
green’), is the chemical element with atomic
number 17 and symbol Cl. It is a halogen,
found in the periodic table in group 17
(formerly VII, VIIa, or VIIb). As the chloride
From Wikipedia, the free encyclopedia
Chlorine
1
ion, which is part of common salt and other
compounds, it is abundant in nature and ne-
cessary to most forms of life, including hu-
mans. In its common elemental form (Cl2 or
"dichlorine")
under
standard conditions.
Chlorine is a powerful oxidant and is used in
bleaching