Real niggaz united - Start making your own internet bussines today! Be your own boss! Join our website and start learn HOW! - Speed Wealthy. Forza Motorsport 3 Iso Pc Download on this page.

Silicon is a chemical element with symbol Si and atomic number 14. A hard and brittle crystalline solid with a blue-gray metallic luster, it is a tetravalent metalloid. It is a member of group 14 in the periodic table, along with carbon above it and germanium, tin, lead, and flerovium below.

It is rather unreactive, though less so than germanium, and has great chemical affinity for oxygen; as such, it was first prepared and characterized in pure form only in 1823 by J?ns Jakob Berzelius. Silicon is the eighth most common element in the universe by mass, but very rarely occurs as the pure element in the Earth's crust.

It is most widely distributed in dusts, sands, planetoids, and planets as various forms of silicon dioxide (silica) or silicates. Over 90% of the Earth's crust is composed of silicate minerals, making silicon the second most abundant element in the Earth's crust (about 28% by mass) after oxygen. The outer electron orbital of silicon, like that of carbon, has four valence electrons. Gratis Program Ma.

The 1s, 2s, 2p and 3s subshells are completely filled while the 3p subshell contains two electrons out of a possible six. Silicon is a semiconductor. It has a negative temperature coefficient of resistance, since the number of free charge carriers increases with temperature.