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Silicon [Si] locate me
CAS-ID: 7440-21-3
An: 14 N: 14
Am: 28.0855 g/mol
Group No: 14
Group Name: Metalloids
Block: p-block  Period: 3
State: solid at 298 K
Colour: dark grey with a bluish tinge Classification: Semi-metallic
Boiling Point: 3173K (2900°C)
Melting Point: 1687K (1414°C)
Density: 2.33g/cm3
Discovery Information
Who: Jons Berzelius
When: 1823
Where: Sweden
Name Origin
Latin silex, or silicis (meaning what were more generally termed "the flints" or "hard rocks" during the Early Modern era where nowadays we would say "silica" or "silicates")
 "Silicon" in different languages.
Sources
Silicon is the second most abundant element and comprises 25.7% of the earth's crust (oxygen is first). Makes up major portion of clay, granite, feldspar, mica, asbestos, quartz (SiO2), and sand.
Primary producers are Austria, Italy, India, South Africa, Australia, Canada, the USA and Brazil. Every year around 5000 tons of electronics grade silicon is produced.
Abundance
 Universe: 700 ppm (by weight)
 Sun: 900 ppm (by weight)
 Carbonaceous meteorite: 1.4 x 105 ppm
 Earth's Crust: 2.771 x 105 ppm
 Seawater:
   Atlantic surface: 0.03 ppm
   Atlantic deep: 0.82 ppm
   Pacific surface: 0.03 ppm
   Pacific deep: 4.09 ppm
 Human:
   260000 ppb by weight
   58000 ppb by atoms
Uses
Used in glass as silicon dioxide (SiO2). It is used as a semiconductor to make microchips for electronics (like your computer). Silicon is also used in solar cells, tools, cement, LCDs, grease and oils.
History
Silicon (Latin silex, silicis for flint, flint's) was first identified by Antoine Lavoisier in 1787, and was later mistaken by Humphry Davy in 1800 for a compound. In 1811 Gay-Lussac and Thenard probably prepared impure amorphous silicon through the heating of potassium with silicon tetrafluoride. In 1824, Berzelius prepared amorphous silicon using approximately the same method as Lussac. Berzelius also purified the product by repeatedly washing it.
Notes
Silicon carbide (SiC) is one of the hardest substances known.
Hazards
Fine powder is highly flammable.
A serious lung disease known as silicosis often occurred in miners, stonecutters, and others who were engaged in work where siliceous dust was inhaled in great quantities.