ARSENIC

[General | States | Energies | Oxidation & Electrons]
[Appearance & Characteristics | Reactions | Other Forms]
[Radius | Conductivity | Abundance | History]

General

Name Arsenic Symbol As
Atomic number 33 Atomic weight 74.9216
Density @ 293 K 5.72 g/cm3 Atomic volume 13.1 cm3/mol
Group Non-Metal, Nitrogen group Discovered 1600

Back to the top

States

State (s, l, g) s
Melting point 886 K Boiling point K
Heat of fusion ? Heat of vaporization 34.760 kJ/mol

Back to the top

Energies

1st ionization energy 946.5 kJ/mole Electronegativity 2.18
2nd ionization energy 1797.8 kJ/mole Electron affinity 78 kJ/mole
3rd ionization energy 2735.4 kJ/mole Specific heat 0.33 J/gK
Heat atomization 302 kJ/mole atoms

Back to the top

Oxidation & Electrons

Shells 2,8,18,5 Electron configuration [Ar] 3d10 4s2 4p3
Minimum oxidation number -3 Maximum oxidation number 5
Minimum common oxidation number -3 Maximum common oxidation number 5

Back to the top

Appearance & Characteristics

Structure rhombohedral Color gray
Uses photocells (GaAs), poisons Toxicity  
Hardness 3.5 mohs Characteristics semimetal,brittle,3 forms

Back to the top

Reactions

Reaction with air mild, w/ht =>As4O6 Reaction with 6M HCl none
Reaction with 6M HCl none Reaction with 15M HNO3 mild, w/ht =>H3AsO4, NOx
Reaction with 6M NaOH none

Back to the top

Other Forms

Number of isotopes 1 Hydride(s) AsH3
Oxide(s) As2O3 Chloride(s) AsCl3 AsCl5

Back to the top

Radius

Ionic radius (2- ion) pm Ionic radius (1- ion) pm
Atomic radius 120 pm Ionic radius (1+ ion) pm
Ionic radius (2+ ion) pm Ionic radius (3+ ion) 72 pm

Back to the top

Conductivity

Thermal conductivity 50.2 J/m-sec-deg Electrical conductivity 30.03 1/mohm-cm
Polarizability 4.3 A^3

Back to the top

HOME

Ssource Arsenopyrite, enargite (misc) Rel. abund. solar system 0.817 log
Abundance earth's crust 0.3 log Cost, pure 320 $/100g
cost, bulk $/100g

Back to the top

History:

Back to the top

Hosted by www.Geocities.ws

1