Chemicool

As

33

74.9216
Arsenic
General | States | Energies | Oxidation & Electrons |Appearance & Characteristics
Reactions | Other Forms |Radius | Conductivity | Abundance
Encyclopedia Britannica articles

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

States
state (s, l, g) s
melting point 886 K boiling point K
Heat of fusion ? Heat of vaporization 34.760 kJ/mol
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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

Oxidation & Electrons
Shells 2,8,18,5 electron configuration [Ar] 3d10 4s2 4p3
minimum oxidation number -3 maximum oxidation number 5
min. common oxidation no. -3 max. common oxidation no. 5
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Appearance & Characteristics
structure rhombohedral color gray
uses photocells (GaAs), poisons toxicity
hardness 3.5 mohs characteristics semimetal,brittle,3 forms

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
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Other Forms
number of isotopes 1 hydride(s) AsH3
oxide(s) As2O3 chloride(s) AsCl3 AsCl5

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
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Conductivity
thermal conductivity 50.2 J/m-sec-deg electrical conductivity 30.03 1/mohm-cm
polarizability 4.3 A^3

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