Silicon
Element 14 · Metalloid
Silicon built the modern world twice: first as stone, glass, and concrete, then as the purified crystal inside every computer chip and solar panel. As a metalloid it sits on the border of metals and nonmetals, and that in-between nature lets engineers tune its conductivity by adding trace impurities — the doping that makes transistors possible. Silicon is never found pure in nature; it arrives as silica sand and silicate rocks, which make up most of Earth's crust. Beyond electronics, silicones seal bathrooms, glass fills windows, and silicon carbide grinds steel.
Key facts
| Atomic number | 14 |
|---|---|
| Atomic weight | 28.085 |
| Category | Metalloid |
| Group / Period | 14 / 3 |
| Block | p |
| Electron configuration | 1s2 2s2 2p6 3s2 3p2 |
| Common oxidation states | +4, -4 |
| State at STP | Solid |
| Electronegativity | 1.90 |
| Atomic radius | 111 pm |
| Density | 2.329 g/cm³ |
| Melting point | 1414 °C |
| Boiling point | 3265 °C |
Occurrence
Silicon is about 28 percent of Earth's crust by mass, mostly as quartz sand and silicate minerals. Purified metallurgical-grade silicon is refined further for the electronics industry.
Applications
Computer chips and transistors
Solar cells
Glass and ceramics
Silicone sealants and polymers
Concrete and construction
Common compounds
- Silicon dioxide (SiO2)
- Silicon carbide (SiC)
- Silicone polymers
- Sodium silicate (Na2SiO3)
A single grain of beach sand and the processor in a phone share the same chemistry: silicon dioxide refined into pure silicon.
Data source: IUPAC standard atomic weights 2021