Atomic Number: 14 Period Number: 3 Group Number: 14
Silicon is a gray and hard semi-metal with very high melting and boiling points. It is the second abundant element in the crust. Most of silicon is always found in silicate minerals and some of them found as silicon oxide. There are three isotopes of silicon in nature: 28Si, 29Si, 30Si and the most abundant one is 28Si, which occupies 92%.
Two allotropes of silicon exist at room temperature: amorphous and crystalline. Amorphous appears as a brown powder while crystalline silicon has a metallic luster and a grayish color. Single crystals of crystalline silicon can be grown with a process known as the Czochralski process. They are used to manufacture of solid-state electronic devices, such as transistors, solar cells, rectifiers and microchips.
Silicon represents one of those elements that has a half full set of electron orbitals for its electrons. This makes its bonding choices in chemical compounds diverse and means that those products are also as diverse. As a dioxide it is called sand. When used as the basis of a semiconductor and infused with another element, it can show opposite electrical properties. It forms compounds with excellent lubrications properties and is sold as such as well.
There are other useful silicon compounds. Silicon carbide (SiC) is nearly as hard as diamond and is used as an abrasive. Sodium silicate (Na2SiO3), also known as water glass, is used in the production of soaps, adhesives and as an egg preservative. Silicon tetrachloride (SiCl4) is used to create smoke screens.
Physical and Chemical properties:
Atomic Weight: 28.0855
Melting Point: 1687 K
Boiling Point: 3538 K
Density: 2.3296 g/cm3
Phase at Room Temperature: Solid
Ionization Energy: 8.152 eV
Oxidation States: +4, +2, -4
See also:
Wikipedia - Basics on Silicon
WebElements - The basic elements of Silicon
Jefferson Lab - Learning about Silicon
