Facts about Silicon - Properties and Uses
Silicon is a non-metallic element found in abundance in the earth’s crust. Silicon is produced during the last stages of the life of a star when it completely burns out.
The name "Silicon" is derived from the Latin name silex or silicis meaning flint or hard stone. It is the second most abundant element in the earth's crust, about 28.2 % of the earth’s crust is made up of silicon.
In the ancient times, silicon was used by Egyptians to make beads and vases. The manufacture of glass using silicon was carried out by Egyptians and Phoenicians as early as 1500 BC.
China and United States produce the maximum amount of Silicon as compared to other nations.
Discovery of Silicon
The raw form of silicon was discovered by Gay Lussac and Louis Jacques Thenard in 1811.
In 1824 Jons Jacob Berzelius was the first person to be able to prepare a pure form of amorphous silicon by heating potassium with silicon tetrafluoride. He then repeatedly washed silicon tetrafluoride till he was able to obtain a pure form of amorphous silicon.
Henri Etienne Sainte-Claire Deville prepared a form of crystalline silicon (the second allotropic form of silicon) in 1854.
How Does Silicon Occur In the Earth's Crust?
Silicon does not exist in its pure form; it exists in combination with other elements as compounds.
Silicon exists in two forms at room temperature – amorphous and crystalline.
- amorphous silicon is a brown colored powder
- crystalline silicon has a metal like shine
Silicon dioxide is the most common form of silicon that occurs in the form of sand, quartz, opal, crystal, amethyst, agate, flint and jasper.
Silicate minerals such as granite, hornblende, asbestos, feldspar, clay, and mica have silicon as one of their main components. They are present in the upper crust and mantle of the earth.
Silicate minerals form the major components of most igneous rocks and are also found in sedimentary and metamorphic rocks.
Silicates have been found in lunar samples, meteorites, and asteroids.
Properties of Silicon
Silicon is represented by the symbol Si and occupies the 14th place in the periodic table. When silicon is mixed with other metals, it strengthens and increases the hardness of the other metal
Silicon is an inert element that does not react with most substances except Hydrofluoric acid, halogens, and dilute alkali.
Silicon is a semiconductor, the conductivity increases with increase in temperature. This property makes Silicon an important component of electronics.
Three isotopes of silicon occur naturally –silicon-28, silicon-29 and silicon-30. Isotopes are two or more forms of an element.
Importance of Single Crystal Silicon
Single Crystal Silicon is used in the production of the microelectronics such as computer chips, semiconductors, etc.
It is made up of continuous unbroken crystals that are produced from the purest form of silicon or doped silicon (silicon with tiny quantities of other elements).
Single-crystal silicon is manufactured using the “Czochralski” process that grows silicon in the shape of cylinders that are up to 2 m long and 45 cm wide. The silicon cylinder is then cut into thin single slice wafers onto which microcircuits are mounted.
Uses of Silicon
1. Sand is composed of silicon dioxide (silica). Sand is used in the manufacture of glass and the construction of buildings.
2. Silicon that is highly pure is combined with boron, gallium, phosphorus and arsenic to produce a form of silicon used in transistors, solar cells, circuit boards and other components utilized in the electronic industry.
3. Silicon is used in the manufacture of silicone. Silicone is a synthetic polymer that has many uses. Using silicon as one of the main ingredients, silicone is produced in the form of fluids, resins or elastomers (rubbers).
Silicon in a Glance
- silicon is a non-metallic element
- about 28.2 % of the earth’s crust is made up of silicon
- silicon is the second most abundant element in the universe
- silicon is made in the last stages of the life of a star when it completely burns out
- silicon does not exist in its pure form; it exists in combination with other elements as compounds
- it is an inert element that does not react with most substances
- silicon is used in the manufacture of silicone that has many uses
- silicon is non-toxic
- silicone is used in cosmetic surgery for breast implants
- the name Silicon Valley is based on silicon because silicon is one of the materials used in the manufacture of computer chips
Uses of Silicon in the Form of Silicone
1. Silicone fluids are used in motor oils and heat transfer liquids. They are used to manufacture hydraulic fluids, paints, varnishes, car waxes and furniture polishes.
2. Silicone resins are used for coating non-stick cookware and industrial molds. They are used for electrical insulation of varnishes for motor and transformer windings.
Silicone resins are utilized in the textile industry to make water-repellent fabrics.
3. In the field of medicine, Silicone is used in the manufacture of surgical implants and dental impression materials. They are used to make glass containers for blood collection, prosthetic devices, gels, and bandages. Silicone is not toxic. Due to this nature, they are used in cosmetic surgery.
4. In the cosmetic industry, Silicone is used in products such as shampoos, shaving gels, hair conditioners and any other gel-like products.
5 Aquariums and other watertight containers use silicone to seal the joint area. Water pipes, faucets, counter joints, and tiles are sealed with silicone to prevent leakage.
© 2014 Nithya Venkat