Si
Silicon is a metalloid that forms the backbone of modern electronics and is the second most abundant element in Earth's crust.
Physical Properties
| Atomic Mass | 28.085 u |
| Density | 2.3296 g/cm³ |
| Melting Point | 1687.0 K |
| Boiling Point | 3538.0 K |
| Appearance | Crystalline, reflective blue-gray metallic |
| State at Room Temp | Solid |
Chemical Properties
| Electronegativity | 1.9 (Pauling) |
| 1st Ionization Energy | 786.5 kJ/mol |
| Electron Affinity | 133.6 kJ/mol |
| Oxidation States | -4, -3, -2, -1, +1, +2, +3, +4 |
Atomic Properties
| Electron Configuration | [Ne] 3s2 3p2 |
| Atomic Radius | 111.0 pm |
| Covalent Radius | 111.0 pm |
| Van der Waals Radius | 210.0 pm |
Discovery
| Discovered By | Jons Jacob Berzelius |
| Discovery Year | 1824 |
| Location | Stockholm, Sweden |
| Named After | Latin 'silex' meaning flint or hard stone |
About Silicon
Silicon is a hard, brittle crystalline solid with a blue-gray metallic luster. It is the second most abundant element in Earth's crust after oxygen. Ultra-pure silicon is essential for semiconductor devices. Silicon plays a role in biology for diatoms and some plants.
Uses & Applications
Semiconductors and computer chips, solar cells, silicone rubber and sealants, glass manufacturing, and concrete.
Fun Fact
Silicon Valley is named after this element because it is the key material in the semiconductor chips that power the tech industry.
Isotopes
| Mass Number | Abundance | Half-Life | Stable |
| 28 | 0.92223% | - | Yes |
| 29 | 0.04685% | - | Yes |
| 30 | 0.03092% | - | Yes |
Electron Configuration
[Ne] 3s2 3p2