Silicon
Definition and meaning of Silicon in chemistry.
![Silicon element card: symbol Si, atomic number 14, atomic mass 28.085, electron configuration [Ne] 3s² 3p², oxidation states +4 -4, Metalloid, group 14, period 3, solid at room temperature.](/assets/images/terms/silicon-chemical-element.webp)
Silicon is a hard, brittle, blue-gray crystalline solid with the chemical symbol Si and atomic number 14. Scientists classify it as a metalloid, meaning it shares properties of both metals and nonmetals. Its remarkable semiconductor properties make it the foundational material for modern electronics.
In more detail
Silicon sits in group 14 of the periodic table. You can find it located directly between carbon and germanium. It is the second most abundant element in the Earth's crust by mass.
However, it almost never occurs in nature as a pure, free element. Instead, you primarily find it as silica or complex silicate minerals. Silicon is famous for its highly useful semiconductor properties.
A semiconductor can conduct electricity under specific conditions but not others. Silicon's electrical conductivity is strongly sensitive to temperature changes. Engineers also alter its conductivity by deliberately introducing chemical impurities.
Scientists call this intentional mixing process doping. Chemically, silicon forms extremely strong covalent bonds with oxygen. These strong chemical bonds create a vast array of complex silicate structures.
These silicate structures dominate everyday geological materials and solid rock formations. Silicon remains relatively unreactive at regular room temperature. However, it reacts vigorously with halogens and dilute alkalis under elevated temperature conditions.
Silicon features a rigid network of covalent chemical bonds. This strong structure contributes to a remarkably high melting point and immense mechanical hardness. Its distinct crystalline geometry perfectly mirrors the diamond cubic crystal structure of carbon.
Key facts
| Field | General Chemistry |
|---|---|
| Symbol | Si |
| Atomic number | 14 |
| Atomic mass | 28.085 u |
| Category | Metalloid |
| Melting point | 1414 °C (2577 °F) |
| Year discovered | 1824 |
Silicon is the absolute foundational material for all modern solid-state electronics. Manufacturers slice pure silicon into extremely thin wafers. They use these flat wafers to build complex computer microchips and tiny transistors. They also use silicon substrates extensively to manufacture photovoltaic solar cells for clean energy.
Frequently asked questions
Is silicon a metal or a nonmetal?
Silicon is a metalloid. This means it has physical and chemical properties right between metals and nonmetals. It is most famous for functioning as a semiconductor.
How is silicon different from silicone?
Silicon is a naturally occurring chemical element. Silicone is a synthetic polymer made of silicon, oxygen, carbon, and hydrogen. People use silicone for sealants and lubricants.
Related terms
Sources & references
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