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Technical data for Chlorine

Click any property name to see plots of that property for all the elements.

Overview
NameChlorine
SymbolCl
Atomic Number17
Atomic Weight35.45
Density3.214 g/l[note]
Melting Point-101.5 °C
Boiling Point-34.04 °C

Thermal properties
PhaseGas
Melting Point-101.5 °C
Boiling Point-34.04 °C
Absolute Melting Point171.6 K
Absolute Boiling Point239.11 K
Critical Pressure7.991 MPa (78.87 Atm)
Critical Temperature416.9 K
Heat of Fusion3.2 kJ/mol
Heat of Vaporization10.2 kJ/mol
Specific Heat478.2 J/(kg K)[note]
Adiabatic Index7/5
Neel PointN/A
Thermal Conductivity0.0089 W/(m K)
Thermal ExpansionN/A

Bulk physical properties
Density3.214 g/l[note]
Density (Liquid)N/A
Molar Volume0.01103
Brinell HardnessN/A
Mohs HardnessN/A
Vickers HardnessN/A
Bulk Modulus1.1 GPa
Shear ModulusN/A
Young ModulusN/A
Poisson RatioN/A
Refractive Index1.000773
Speed of Sound206 m/s
Thermal Conductivity0.0089 W/(m K)
Thermal ExpansionN/A

Reactivity
Valence5
Electronegativity3.16
ElectronAffinity349 kJ/mol
Ionization Energies
1251.2, 2298, 3822, 5158.6, 6542, 9362, 11018, 33604, 38600, 43961 kJ/mol

Health and Safety
DOT Hazard ClassN/A
DOT NumbersN/A
RTECS Number
RTECSFO2100000
NFPA LabelN/A

Classifications
Alternate NamesNone
Names of AllotropesDichlorine
Blockp
Group17
Period3
SeriesHalogen
Electron Configuration[Ne]3s23p5
ColorYellow
Discovery
1774 in Sweden
Gas phaseDiatomic
CAS NumberCAS7782-50-5
CID Number
CID24526
RTECS Number
RTECSFO2100000

Electrical properties
Electrical TypeInsulator
Electrical Conductivity0.01 S/m
Resistivity100 m Ω
Superconducting PointN/A

Magnetic properties
Magnetic TypeDiamagnetic
Curie PointN/A
Mass Magnetic Susceptibility-7.2×10-9 m3/Kg
Molar Magnetic Susceptibility-5.11×10-10 m3/mol
Volume Magnetic Susceptibility-2.31×10-8

Abundances
% in Universe0.0001%
% in Sun0.0008%
% in Meteorites0.037%
% in Earth's Crust0.017%
% in Oceans2%
% in Humans0.12%

Atomic dimensions and structure
Atomic Radius79 pm
Covalent Radius102 pm
Van der Waals Radius175 pm
Crystal StructureBase Orthorhombic
Lattice Angles
π/2, π/2, π/2
Lattice Constants
622.35, 445.61, 817.85 pm
Space Group NameCmca
Space Group Number64

Nuclear Properties
Half-LifeStable
LifetimeStable
Decay ModeN/A
Quantum Numbers2P3/2
Neutron Cross Section35.3
Neutron Mass Absorption0.033
Known Isotopes
28Cl, 29Cl, 30Cl, 31Cl, 32Cl, 33Cl, 34Cl, 35Cl, 36Cl, 37Cl, 38Cl, 39Cl, 40Cl, 41Cl, 42Cl, 43Cl, 44Cl, 45Cl, 46Cl, 47Cl, 48Cl, 49Cl, 50Cl, 51Cl
Stable Isotopes
35Cl, 37Cl
Isotopic Abundances
35Cl75.78%
37Cl24.22%


Notes on the properties of Chlorine:

Density: Density given for Cl at 0° Celsius. 2

Specific Heat: gas (Cl ) 2

Up to date, curated data provided by Mathematica's ElementData function from Wolfram Research, Inc.

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