Se

SELENIUM

Definition From 'selene' or moon.it varies in conductivitywith the intensity of light making uselful in photoelectric device.

Discovery 1817 by jons jakob bercelius of sweden

Uses copy machines, semiconductor

Group of Elements Non-metals(Solid)

Atomic Weight 78.96

Oxidation State -2,+4,6

Melting Point 217

Boiling Point 685

Density 4.82 g/cm3

Electronegativity 2.4