Selenium

A chemical element, in the periodic table Selenium has the symbol Se and the atomic number 34. Selenium is derived from "selene," the latin word for the Moon.

Selenium was discovered in 1817 by Jons Jacob Berzelius, and is an essential micronutrient in all known forms of life; it is a component of the unusual amino acid selenocysteine.

Properties

Symbol: Se

Atomic Number: 34

Atomic Mass: 78.96

Number of outer energy levels electrons: 6

State of Matter: Solid

When it was discovered: in 1817 in Sweden

Uses: Xerography and medicines

Density: 4.79

Specific Gravity: 4.25

Melting Point: 50 degress

Appearance: silver, like a soft metalliod, but its not metal

other facts: toxic