Element 14

Silicon (Si)

Metalloid · Period 3 · Group 14 · p-block

Silicon (Si) is element 14 of the periodic table, a metalloid in period 3, group 14 (p-block) with an atomic mass of 28.085 and is a solid at standard conditions.

At a glance

Atomic number
14
Symbol
Si
Atomic mass
28.085 u
Category
Metalloids
Period
3
Group
14
Block
p-block
Phase at STP
solid

Electron structure

Electron configuration
1s2 2s2 2p6 3s2 3p2
Shorthand configuration
[Ne] 3s2 3p2
Electrons per shell
2, 8, 4
Oxidation states
-4, -3, -2, -1, +1, +2, +3, +4

Physical properties

Melting point
1,687 K (1,413.85 °C)
Boiling point
3,538 K (3,264.85 °C)
Density
2.3296 g/cm³
Phase
solid

Atomic properties

Electronegativity (Pauling)
1.9
Atomic radius
111 pm
Covalent radius
111 pm
Van der Waals radius
210 pm
First ionization energy
786 kJ/mol
Electron affinity
134 kJ/mol

Notable isotopes

Notable isotopes of Silicon: mass number, atomic mass, natural abundance, and stability.
IsotopeMassAbundanceStability
Si-2827.9769392.23%Stable

Common uses

  • Computer chips
  • Solar cells
  • Glass
  • Silicones

Discovery

Year
1824
Discovered by
Jöns Jacob Berzelius
Country
Sweden

Frequently asked questions

Is silicon a metal?
Silicon is a metalloid, which means it shows properties of both metals and nonmetals.
How many protons does silicon have?
Silicon has 14 protons. Its atomic number is 14, which is also the number of electrons in a neutral atom of silicon.
What group and period is silicon in?
Silicon is in group 14 and period 3 of the periodic table, in the p-block.
What is the atomic mass of silicon?
The atomic mass of silicon is 28.085 u (unified atomic mass units).

Keep exploring

Silicon's row is on the printable element property sheet, and its tile is on the periodic table wall chart - the same numbers as above, laid out for A4 or A3 paper.