Name: silicon	Group number: 14
Symbol: Si	Group name: (none)
Atomic number: 14	Period number: 3
Atomic weight: 28.0855 (3) r	Block: p-block
CAS Registry ID: 7440-21-3	Voice:
Standard state: solid at 298 K	Colour: dark grey with a bluish tinge
Classification: Semi-metallic	Availability:

Isolation

There is normally no need to make silicon in the laboratory as it is readily available commercially. Silicon is readily available through the treatment of silica, SiO₂, with pure graphite (as coke) in an electric furnace.

SiO₂ + 2C Si + 2CO

Under these conditions, silicon carbide, SiC, can form. However, provided the amount of SiO₂ is kept high, silicon carbide may be eliminated.

2SiC + SiO₂ 3Si + 2CO

Very pure silicon can be made by the reaction of SiCl₄ with hydrogen, followed by zone refining of the resultant silicon.

SiCl₄ + 2H₂ Si + 4HCl