Discovery date : 1824
Discovered by: Jöns Jacob Berzelius
Origin of the name: The name is derived from the Latin 'silex' or 'silicis', meaning flint.
Allotropes : amorphous Si, crystalline Si
~>SILICON s a chemical element with symbol Si and atomic number 14. A hard and brittle crystalline solid with a blue-grey metallic lustre, it is a tetravalent metalloid and semiconductor.
| FACT BOX | |||
| Group | 14 | Melting point | 1414°C, 2577°F, 1687 K |
| Period | 3 | Boiling point | 3265°C, 5909°F, 3538 K |
| Block | p | Density (g cm−3) | 2.3296 |
| Atomic number | 14 | Relative atomic mass | 28.085 |
| State at 20°C | Solid | Key isotopes | 28Si, 30Si |
| Electron configuration | [Ne] 3s23p2 | CAS number | 7440-21-3 |
| ChemSpider ID | 4574465 | ChemSpider is a free chemical structure database | |
Silica (SiO2) in the form of sharp flints were among the first tools made by humans. The ancient civilizations used other forms of silica such as rock crystal, and knew how to turn sand into glass. Considering silicon’s abundance, it is somewhat surprising that it aroused little curiosity among early chemists.
Attempts to reduce silica to its components by electrolysis had failed. In 1811, Joseph Gay Lussac and Louis Jacques Thénard reacted silicon tetrachloride with potassium metal and produced some very impure form of silicon. The credit for discovering silicon really goes to the Swedish chemist Jöns Jacob Berzelius of Stockholm who, in 1824, obtained silicon by heating potassium fluorosilicate with potassium. The product was contaminated with potassium silicide, but he removed this by stirring it with water, with which it reacts, and thereby obtained relatively pure silicon powder.