---
title: "Silicon (Si) — element 14"
description: "Silicon is element 14, symbol Si, atomic weight 28.085. Configuration, properties, uses and neighbours."
url: https://atoneplace.net/element/silicon/
site: "At One Place"
---

# Silicon (Si)

**Silicon — element 14: Si**

28.085 u · Metalloid · period 3, group 14

Silicon is the second most abundant element in the crust at about 28% by mass, and essentially all of it is bonded to oxygen — sand, quartz, granite, clay and glass are all silicon-oxygen frameworks. The wafers used for chips are grown as single crystals up to 300 mm across and are among the purest bulk materials ever made, at better than one impurity atom in a billion. Silicon is a poor conductor and a poor insulator, and that awkward middle position, plus an oxide that happens to be an excellent insulator, is the entire reason the semiconductor industry is built on it rather than on germanium.

## Properties

- **Atomic number:** 14
- **Symbol:** Si
- **Standard atomic weight:** 28.085 u
- **Category:** Metalloid
- **Group:** 14
- **Period:** 3
- **Block:** p-block
- **Electron configuration:** [Ne] 3s² 3p²
- **Electrons per shell:** 2, 8, 4
- **Melting point:** 1,687 K — 1413.8 °C — 2576.9 °F
- **Boiling point:** 3,538 K — 3264.8 °C — 5908.7 °F
- **Density:** 2.3296 g/cm³
- **Electronegativity:** 1.9 (Pauling)
- **Oxidation states:** +4, +2, -4
- **Discovered:** 1824 by Jöns Jacob Berzelius

## Electron configuration

- **Full:** 1s² 2s² 2p⁶ 3s² 3p²
- **Noble gas shorthand:** [Ne] 3s² 3p²
- **Shells:** K: 2 · L: 8 · M: 4

## What it is used for

- Integrated circuits and solar cells
- Silicone rubber, sealants and lubricants
- Glass, which is mostly silicon dioxide
- Ferrosilicon as a deoxidiser in steelmaking
- Silicon carbide abrasives and power semiconductors

> IUPAC publishes an interval, [28.084, 28.086]; 28.085 is the conventional value. Silicon and silicone are different things: the element, and a family of synthetic polymers built on silicon-oxygen chains.

## Neighbours in the table

| Z | Element | Symbol | Mass |
| --- | --- | --- | --- |
| 12 | Magnesium | Mg | 24.305 |
| 13 | Aluminum | Al | 26.982 |
| 14 | Silicon ← | Si | 28.085 |
| 15 | Phosphorus | P | 30.974 |
| 16 | Sulfur | S | 32.06 |

## Group 14

Elements in the same group share their outer electron count, which is why they behave similarly in reactions. Silicon sits in group 14 with carbon, germanium, tin, lead, flerovium.

## Common questions

### What is the atomic number of silicon?

14. That is the number of protons in its nucleus, which is what defines the element.

### What is the symbol for silicon?

Si.

### What is the electron configuration of silicon?

1s² 2s² 2p⁶ 3s² 3p², or [Ne] 3s² 3p² in noble-gas shorthand.

### What is the melting point of silicon?

1,687 K — 1413.8 °C — 2576.9 °F

## Related pages

- [Magnesium (Mg)](https://atoneplace.net/element/magnesium/)
- [Aluminum (Al)](https://atoneplace.net/element/aluminum/)
- [Phosphorus (P)](https://atoneplace.net/element/phosphorus/)
- [Sulfur (S)](https://atoneplace.net/element/sulfur/)
- [Carbon (C)](https://atoneplace.net/element/carbon/)
- [Germanium (Ge)](https://atoneplace.net/element/germanium/)
- [Tin (Sn)](https://atoneplace.net/element/tin/)
- [Lead (Pb)](https://atoneplace.net/element/lead/)
- [Flerovium (Fl)](https://atoneplace.net/element/flerovium/)

## Sources

- Official vendor product documentation — At One Place (/about/)