Silicon (Si)
Silicon is the second most abundant element in Earth's crust and the heart of nearly every computer chip.
Silicon properties
- Atomic mass
- 28.085 u
- Category
- Metalloid
- Group
- 14
- Period
- 3
- Block
- p-block
- State at room temp.
- Solid
- Melting point
- 1,687 K (1,413.8 °C)
- Boiling point
- 3,538 K (3,264.8 °C)
- Density
- 2.329 g/cm³
- Common charges
- +4, −4
- Oxidation states
- +4, +2, −4
- Atomic radius
- 210 pm
- Ionization energy
- 8.152 eV
- Electron affinity
- 1.385 eV
- Radioactive
- No, has stable isotopes
- Discovered
- 1823
Silicon electron configuration
- Electron configuration
- [Ne] 3s2 3p2
- Full electron configuration
- 1s2 2s2 2p6 3s2 3p2
- Electron shells
- 2 · 8 · 4
The electron configuration of Silicon (Si) is [Ne] 3s2 3p2. Its 14 electrons are arranged in shells as 2, 8, 4.
Protons, neutrons and electrons in Silicon
A neutral Silicon atom has 14 protons and 14 electrons. Most Silicon atoms have about 14 neutrons: the atomic mass rounded to 28, minus the atomic number 14.
Neutrons are approximate: atoms of the same element can have different numbers of neutrons (isotopes). Atomic number and mass
How many valence electrons does Silicon have?
4
Silicon has 4 valence electrons in its outermost shell, shell 3. These are the electrons involved in chemical bonding.
Silicon orbital diagram
Each box is an orbital that holds up to two electrons with opposite spins (↑↓). The inner shells are the same as the noble gas in brackets. How to write electron configurations
Molar mass of Silicon
28.085 g/mol
One mole of Silicon atoms (6.022 × 10²³ atoms) has a mass of 28.085 grams. Use this value to convert between grams and moles.
Compounds containing Silicon
Silicon facts
- Silicon is the second most abundant element in Earth's crust and the heart of nearly every computer chip.
- Silicon (Si) has atomic number 14 and is a solid at room temperature. It was discovered in 1823.
Position in the periodic table
Silicon is element 14, in period 3 and group 14 of the periodic table, in the p-block.
Uses of Silicon
Silicon is the key ingredient of most solar cells, which are made from thin wafers of very pure crystalline silicon. It is alloyed with aluminum for cast engine parts and with iron, as ferrosilicon, in steelmaking. Silica (silicon dioxide) sand is the main raw material for glass and is used in concrete, and silicon is also made into silicones for sealants, lubricants and bakeware.
Who discovered Silicon?
Swedish chemist Jöns Jacob Berzelius is credited with isolating silicon in 1823 in Stockholm, by heating potassium fluorosilicate with potassium metal.
Where does the name come from?
Silicon comes from the Latin silex (genitive silicis), meaning 'flint', a hard stone made largely of silica. Thomas Thomson gave it the -on ending in 1817 to match carbon and boron, nonmetals it resembles.
Same group
Compare Silicon
FAQ
What is the electron configuration of Silicon?
The electron configuration of Silicon (Si) is [Ne] 3s2 3p2. Its 14 electrons are arranged in shells as 2, 8, 4.
How many protons, neutrons and electrons does Silicon have?
A neutral Silicon atom has 14 protons and 14 electrons. Most Silicon atoms have about 14 neutrons: the atomic mass rounded to 28, minus the atomic number 14.
How many valence electrons does Silicon have?
Silicon has 4 valence electrons in its outermost shell, shell 3. These are the electrons involved in chemical bonding.
What is the molar mass of Silicon?
The molar mass of Silicon is 28.085 g/mol. This is the same number as its atomic mass, 28.085 u.
Is Silicon a metal?
Not exactly. Silicon is a metalloid, with properties between those of metals and nonmetals.
Is Silicon radioactive?
Ordinary Silicon is not radioactive: it has at least one stable isotope. Like every element, it also has radioactive isotopes, most of them made in laboratories.
Where is Silicon on the periodic table?
Silicon is element 14, in period 3 and group 14 of the periodic table, in the p-block.