Acetylene (C2H2): Structure, Properties, Preparation, Uses, Health Hazards

Acetylene is also called ethyne or narcyrene or vinylene. It is also used as a building block in industries related to chemicals. It also has its application as a fuel. It is unstable in its pure form and should be treated as a solution. It is an unsaturated compound in which two carbon atoms are connected by a double bond. It is unstable in its basic form and is used as a solution. This compound is unsaturated. The two carbon atoms that make it up are connected by two bonds.

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This Story also Contains

1. Other Names Of Acetylene(C2H2)
2. C2H2 Structure
3. Properties Of Acetylene(C2H2)
4. Preparation Of Acetylene(C2H2)
5. Chemical Properties Of Acetylene(C2H2)
6. Acetylene Uses-C2H2
7. Health Hazards Of C2H2

Vinylene is a colourless gas with an ether-like odour. Easily soluble in chloroform, water, acetone and benzene. Something is dissolved in carbon disulfide or alcohol. It is lighter than air and can catch fire. Prolonged exposure to flame or heat can cause rapid rupture of the container.

Other Names Of Acetylene(C2H2)

1. Ethyne

2. Nar Cyrene

3. Vinylene

C2H2 Structure

Acetylene has a triple bond between its 2 carbon atoms. There are 2 pi bonds and 1 sigma bond between these carbon atoms. A carbon atom can form only 4 covalent bonds, so the molecule has a linear geometry (acetylene has a triple bond and a C-H single bond, which results in the formation of the linear molecule). Hence, the atoms of the carbon present in the acetylene molecule have sp hybridization.

Properties Of Acetylene(C2H2)

• The chemical formula for acetylene is C2H2.

• 26.038 g mol-1 is the molar mass of acetylene.

• Colourless liquid.

• Odourless.

• 1.1772 g/L is the density of acetylene.

• The melting point of acetylene is -80.8 °C.

• Soluble in alcohol and benzene.

• The vapour pressure of acetylene is 44.2 atmospheres.

• The acidity of acetylene is 25.

• The magnetic susceptibility of acetylene is -20.8×10-6 cm3/mol.

Preparation Of Acetylene(C2H2)

Since 1950, this compound has been synthesised by partial combustion of CH4 (methane). About 4,00,000 tons were produced by 1983.It is produced by a reaction discovered by Friedrich Wöllate in 1862. The hydrolysis reaction of calcium carbide is as follows-

CaC2 + 2H2O → Ca(OH)2+ C2H2

The above reaction is carried out at very high temperatures of about 2000°C using an electric arc furnace.

Chemical Properties Of Acetylene(C2H2)

1. Reaction with HBr

Treatment of acetylene with HBr yields ethylidene bromide.

2. Reactions with Sodium Metal

Sodium reacts with acetylene to form sodium hydro acetylide and hydrogen.

3. Reaction with HCl

CH3CHCl2 is formed when acetylene reacts with HCl.

Acetylene Uses-C2H2

• Acetylene is used in brazing.

• It has it’s application in the glass industry.

• It is also used in the manufacturing of synthetic rubber.

• Used for soldering metals.

• It is also used as an additive to preserve food.

• For metal deposition.

• Used in the manufacture of acetic acid.

• It is used as a raw material for the production of acrylonitrile.

• Used for carburizing steel.

• It can also be used as a fuel additive.

• Lamps, oxy-fuel welding, metal cutting and soldering.

• Used in metallurgical processes for brazing, metallizing and hardening, flame scarring and localised heating.

• Flames are also used in glass making.

• Chemically, acetylene can be used to make synthetic rubber, butyrolactone, vinyl alkyl ethers, and pyrrolidones.

• Used in soldering, local heating and glass industry.

Health Hazards Of C2H2

Persons in contact with this compound may experience headache, unconsciousness and dizziness. High levels of ethyne in the air can cause suffocation.