Name :  Arsenic
Symbol :  As
Atomic Number :  33
Atomic Weight :  74.92159
Specific Heat :  0.33 J/gK
Melting Point :  817°C @ 28 atmos.
Vaporization :  34.760 kJ/mol
Boiling Point :  Sublimes at 613°C
Electronegativity :  2.18
Density@293 K :  5.72 g/cm³
Discovered :  Known to the ancients
Description :  Steel-gray, brittle semi-metal.
Uses :  Many of its compounds are deadly poison and used as weed killer and rat poison. Conducts electricity. Used in semiconductors. Some compounds, called arsenides, are used in the manufacture of paints, wallpapers, and ceramics.