Arsenic (thing)

(From the Greek arsenikon, "yellow orpiment") A silvery-white, brittle, very poisonous, nonmetallic chemical element of the nitrogen family, compounds of which are used in making pesticides, glass, medicines, etc. It is also used in some lead alloys and in semiconductors, especially as gallium arsenide. The name is commonly applied to the highly poisonous arsenic trioxide, used for rodent control.

Symbol: As
Atomic number: 33
Atomic weight: 74.92160
Density (at room temperature and pressure): 5.73 g/cc
Melting point (at 28 standard atmospheres of pressure): 817°C
Boiling point: sublimes at 614°C
Main valence: +3, +5
Ground state electron configuration: [Ar]3d¹⁰4s²4p³