Silicon (Si)
Element 14 · metalloid · group 14, period 3
Silicon is element 14, a metalloid in group 14 and period 3. Its electron configuration is [Ne] 3s2 3p2. That leaves 4 valence electrons in the outer shell, with the shells filling 2, 8, 4. With 4 to gain and 4 to lose it is equally far from either, so it shares electrons in covalent bonds rather than forming ions. The charges listed for it, +4, are oxidation states rather than charges it usually carries.
- 14 protons
- 4 valence e−
- +4
- p-block
Properties
| Atomic number | 14 |
|---|---|
| Symbol | Si |
| Standard atomic weight | 28.085 u |
| Group | 14 |
| Period | 3 |
| Block | p-block |
| Category | metalloid |
| Electron configuration | 1s2 2s2 2p6 3s2 3p2 |
| Noble-gas notation | [Ne] 3s2 3p2 |
| Electrons per shell | 2, 8, 4 |
| Valence electrons | 4 |
| Common ionic charge | +4 |
| Electronegativity (Pauling) | 1.9 |
| Protons / electrons | 14 / 14 |
Electron configuration of silicon
Orbitals fill from the lowest energy upward. Writing that out for silicon gives 1s2 2s2 2p6 3s2 3p2, which is 1s2 2s2 2p6 3s2 3p2 in plain text.
Everything up to Ne is the same as in that noble gas, so it is usually abbreviated to [Ne] 3s2 3p2. The part outside the bracket is what does the chemistry.
| Subshell | Electrons | Capacity |
|---|---|---|
| 1s | 2 | 2 |
| 2s | 2 | 2 |
| 2p | 6 | 6 |
| 3s | 2 | 2 |
| 3p | 2 | 6 |
Silicon ion charge
Silicon commonly forms ions with a charge of +4.
It has 4 valence electrons, which puts it exactly as far from an empty outer shell as from a full one. Neither route is shorter, so it does not hand electrons over at all - it shares them, which is why it forms 4 covalent bonds. The values above are oxidation states rather than charges it normally carries.
Common questions
How many valence electrons does silicon have?
Silicon has 4 valence electrons. For a main-group element the count is the group number minus 10, and silicon is in group 14.
What is the electron configuration of silicon?
1s2 2s2 2p6 3s2 3p2, or [Ne] 3s2 3p2 written from the previous noble gas. Orbitals fill lowest energy first.
What is the charge of silicon?
Silicon commonly forms ions with a charge of +4. With 4 valence electrons it is exactly as far from an empty shell as from a full one, so neither route is shorter and it shares electrons instead. Those values are oxidation states, not charges it normally carries.
How many protons, electrons and neutrons does silicon have?
A neutral silicon atom has 14 protons and 14 electrons. Its standard atomic weight is 28.085, so the most common isotope has about 14 neutrons.
Nearby elements
See the ionic charge of every element →