Periodic TableAll elementsSilicon
No. 014
Si
28.085 u
Element · Metalloid

Silicon

Silicon (硅, symbol Si) is chemical element number 14, a Metalloid in period 3, group 14 of the periodic table, with a standard atomic weight of about 28.085. Foundation of modern electronics. Second most abundant element in Earth's crust.

Period 3Group 14[Ne] 3s² 3p²

Properties

Atomic number14
SymbolSi
Atomic mass28.085 u
CategoryMetalloid
Period3
Group14
Electron configuration[Ne] 3s² 3p²
Electronegativity1.9
Covalent radius111 pm
Density2.3296 g/cm³
Melting point1687 K
Boiling point3538 K
DiscoveryJöns Jacob Berzelius, 1824

Overview

Foundation of modern electronics. Second most abundant element in Earth's crust. Silicon (Si) is a Metalloid with atomic number 14, located in period 3, group 14. As a metalloid it shares properties of both metals and nonmetals and is a mainstay of semiconductor materials.

Its electron configuration is [Ne] 3s² 3p², with 4 electrons in the outer shell, and an electronegativity of about 1.9 (Pauling). Around 25 °C it is usually a solid; it melts near 1687 K (1413.9 °C), boils near 3538 K (3264.9 °C), has a density around 2.3296 g/cm³.

In industry and daily life it turns up in Electronics / Semiconductors and Structural / Alloys. It was first described by Jöns Jacob Berzelius in 1824. The periodic trends guide explains the underlying patterns.

Electron shells

Si14

Electrons per shell: 2 · 8 · 4

Main uses

Hazard

LowNo special hazard flags.

Compounds containing Silicon

No compounds in this knowledge base contain Silicon yet.

Data sources

Atomic mass uses IUPAC (CIAAW) standard atomic weights; the covalent radius is from Cordero et al. (2008). Verify on the RSC Periodic Table, PubChem and Wikipedia. Educational reference only.