The correct answer is A. Ethine.
Ethyne, also known as acetylene, is a colorless, flammable gas with the chemical formula C2H2. It is the simplest alkyne and the simplest hydrocarbon with a triple bond. Ethyne is used as a fuel, a chemical intermediate, and a lighting gas.
Propane, butane, and methyl are all hydrocarbons that are not used as illuminated gases. Propane is a colorless, odorless gas that is used as a fuel for heating, cooking, and powering engines. Butane is a colorless, flammable gas that is used as a fuel in lighters and camping stoves. Methyl is a colorless, flammable liquid that is used as a solvent and a fuel.
Ethyne is used as an illuminated gas because it is a very flammable gas that burns with a bright flame. It is also a relatively inexpensive gas. Ethyne is used in a variety of applications, including:
- Lighting: Ethyne is used in gas lamps and lanterns.
- Welding: Ethyne is used in oxyacetylene welding.
- Cutting: Ethyne is used in oxyacetylene cutting.
- Heating: Ethyne is used in blowtorches and other heating devices.
- Chemical synthesis: Ethyne is used in the production of a variety of chemicals, including acetaldehyde, acetic acid, and vinyl chloride.