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General Chemistry

Silicon

Definition and meaning of Silicon in chemistry.

Silicon is a chemical element represented by the symbol Si and atomic number 14. It is a hard, brittle crystalline solid with a blue-gray metallic luster and is classified as a metalloid.

In more detail

Silicon is a group 14 element in the p-block of the periodic table, situated directly between carbon and germanium. It is the second most abundant element in the Earth's crust by mass, occurring primarily as silicate minerals and silica rather than as a pure, free element. Silicon exhibits highly useful semiconductor properties, meaning its electrical conductivity is strongly sensitive to temperature changes and the deliberate introduction of impurities through a process called doping. Chemically, it forms extremely strong covalent bonds with oxygen, leading to a vast array of complex silicate structures that dominate geological materials and rock formations. Despite being relatively unreactive at room temperature, silicon reacts vigorously with halogens and dilute alkalis under elevated temperature conditions. Its rigid network covalent structure contributes to a remarkably high melting point, immense mechanical hardness, and distinct crystalline geometry that mirrors the diamond cubic crystal structure of carbon.

Key facts

FieldGeneral Chemistry
SymbolSi
Atomic number14
Atomic mass28.085 u
CategoryMetalloid
State at room temperatureSolid
Melting point1414 °C (2577 °F)
Boiling point3265 °C (5909 °F)
Year discovered1824
Example

Silicon is the foundational material in modern solid-state electronics, serving as the primary semiconductor substrate utilized in manufacturing computer microchips, transistors, and photovoltaic solar cells.

Frequently asked questions

Is silicon a metal or a nonmetal?

Silicon is a metalloid, meaning it has physical and chemical properties intermediate between those of metals and nonmetals, most notably functioning as a semiconductor.

How is silicon different from silicone?

Silicon is a naturally occurring chemical element, while silicone is a synthetic polymer made of silicon, oxygen, carbon, and hydrogen that is used for sealants and lubricants.

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