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Technical data for Arsenic

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Overview
NameArsenic
SymbolAs
Atomic Number33
Atomic Weight74.921595
Density5.727 g/cm3
Melting Point817 °C
Boiling Point614 °C[note]

Thermal properties
PhaseSolid
Melting Point817 °C
Boiling Point614 °C[note]
Absolute Melting Point1090 K
Absolute Boiling Point887 K
Critical PressureN/A
Critical TemperatureN/A
Heat of Fusion27.7 kJ/mol
Heat of Vaporization32.4 kJ/mol
Specific Heat328 J/(kg K)[note]
Adiabatic IndexN/A
Neel PointN/A
Thermal Conductivity50 W/(m K)
Thermal ExpansionN/A

Bulk physical properties
Density5.727 g/cm3
Density (Liquid)5.22 g/cm3
Molar Volume0.000013082
Brinell Hardness1440 MPa
Mohs Hardness3.5
Vickers Hardness1510 MPa[note]
Bulk Modulus22 GPa
Shear ModulusN/A
Young Modulus8 GPa
Poisson RatioN/A
Refractive Index1.001552
Speed of SoundN/A
Thermal Conductivity50 W/(m K)
Thermal ExpansionN/A

Reactivity
Valence5
Electronegativity2.18
ElectronAffinity78 kJ/mol
Ionization Energies
947, 1798, 2735, 4837, 6043, 12310 kJ/mol

Health and Safety
DOT Hazard Class
6.1
DOT Numbers1558
RTECS Number
RTECSCG0525000
NFPA LabelNFPA Label

Classifications
Alternate NamesNone
Names of Allotropes
YellowArsenic, BlackArsenic, GrayArsenic
Blockp
Group15
Period4
SeriesMetalloid
Electron Configuration[Ar]4s23d104p3
ColorSilver
Discovery
1250
Gas phaseN/A
CAS NumberCAS7440-38-2
CID Number
CID5359596
RTECS Number
RTECSCG0525000

Electrical properties
Electrical TypeConductor
Electrical Conductivity3.3×106 S/m
Resistivity3×10-7 m Ω
Superconducting PointN/A

Magnetic properties
Magnetic TypeDiamagnetic
Curie PointN/A
Mass Magnetic Susceptibility-3.9×10-9 m3/Kg
Molar Magnetic Susceptibility-2.92×10-10 m3/mol
Volume Magnetic Susceptibility-0.0000223

Abundances
% in Universe8×10-7%
% in SunN/A
% in Meteorites0.00018%
% in Earth's Crust0.00021%
% in Oceans2.3×10-7%
% in Humans5×10-6%

Atomic dimensions and structure
Atomic Radius114 pm
Covalent Radius119 pm
Van der Waals Radius185 pm
Crystal StructureSimple Trigonal
Lattice Angles
π/2, π/2, 2 π/3
Lattice Constants
375.98, 375.98, 1054.75 pm
Space Group NameR_ 3m
Space Group Number166

Nuclear Properties
Half-LifeStable
LifetimeStable
Decay ModeN/A
Quantum Numbers4S3/2
Neutron Cross Section4.2
Neutron Mass Absorption0.002
Known Isotopes
60As, 61As, 62As, 63As, 64As, 65As, 66As, 67As, 68As, 69As, 70As, 71As, 72As, 73As, 74As, 75As, 76As, 77As, 78As, 79As, 80As, 81As, 82As, 83As, 84As, 85As, 86As, 87As, 88As, 89As, 90As, 91As, 92As
Stable Isotopes
75As
Isotopic Abundances
75As100%


Notes on the properties of Arsenic:

Boiling Point: Arsenic sublimates at this temperature.

Specific Heat: Value given for solid alpha form.

Vickers Hardness: converted from Brinell scale

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

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