Technical data for Arsenic

Overview
NameArsenic
SymbolAs
Atomic Number33
Atomic Weight74.9216
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
Heat of Fusion27.7 kJ/mol
Heat of Vaporization32.4 kJ/mol
Heat of CombustionN/A
Specific Heat328 J/(kg K)[note]
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 MPa
Bulk Modulus22 GPa
Young Modulus8 GPa
Refractive Index1.001552
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
Autoignition PointN/A
FlashpointN/A

Classifications
Alternate NamesNone
Nams of Allotropes
YellowArsenic, BlackArsenic, GrayArsenic
Blockp
Group15
Period4
Electron Configuration[Ar]3d104s24p3
ColorSilver
Discovery
1250
Gas phaseN/A
CAS NumberCAS7440-38-2

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
Molar Magnetic Susceptibility-2.92×10-10
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
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.