Properties

• Colorless and Odorless: Acetylene is a colorless gas, although it is often perceived as having a slight garlic-like odor due to impurities.

• Highly Flammable: Acetylene is extremely flammable and burns with a bright, hot flame, making it useful in welding and cutting applications.

• Lightest Alkyne: Acetylene is the simplest and lightest alkyne hydrocarbon, consisting of two carbon atoms triple-bonded with hydrogen atoms.

• Unstable Under Pressure: Acetylene is unstable at high pressures and requires special handling and storage conditions to prevent decomposition and potential explosions.

• Soluble in Solvents: Acetylene is soluble in certain solvents, such as acetone, and is stored in cylinders dissolved in acetone to stabilize it.

Applications

• Welding and Cutting: Acetylene is primarily used as a fuel in oxy-acetylene welding and cutting, where it provides a very high-temperature flame ideal for metalwork.

• Synthesis of Chemicals: Acetylene is used in the production of various chemicals, including acetic acid, acetaldehyde, and acrylic acid.

• Soldering: Acetylene is used in soldering applications where high temperatures are needed to join metals in electronics and plumbing industries.

• Flame Hardening: Acetylene is used for flame-hardening processes in the manufacturing of tools, machine parts, and steel products.

• Lighting: Historically, acetylene was used in carbide lamps for mining, diving, and railway signals due to its bright, hot flame.

Facts

• Produced from Calcium Carbide: Acetylene is typically produced by reacting calcium carbide with water in a controlled environment, releasing the gas.

• High Flame Temperature: Acetylene's flame temperature can reach around 3,500°C (6,332°F) when burned with oxygen, making it one of the hottest available flame sources.

• Storage and Safety Concerns: Due to its instability under pressure, acetylene is stored in specially designed cylinders filled with porous material and dissolved in acetone to prevent explosive decomposition.

• Historical Use: Acetylene was widely used for lighting before the advent of electric lights, particularly in street lamps and miners' lamps.

• Special Handling Required: Acetylene requires careful handling and monitoring due to its flammable and explosive nature, especially in confined spaces or high-pressure environments.