CH3CHCH3CH3

CH3CHCH3CH3 is the condensed structural formula for isobutane, also known as 2-methylpropane. It has the chemical formula C4H10 and is one of the isomers of butane. In IUPAC nomenclature, the preferred name is 2-methylpropane; common names include isobutane and methylpropane.

Structure and classification

Isobutane is a branched alkane. Its carbon skeleton consists of a central carbon atom bonded to three methyl groups (CH3) and one hydrogen, giving it a compact, three-pronged shape. This branching distinguishes it from n-butane, the straight-chain isomer. As a hydrocarbon, isobutane is nonpolar and typically exists as a colorless, odorless gas at standard conditions, readily liquefying under modest pressure.

Occurrence, production, and uses

Isobutane is produced during petroleum refining and natural gas processing and is a major component of liquefied petroleum gas (LPG). It serves as a fuel in heating and cooking applications and as a propellant in various aerosol products. It is also used as a refrigerant under the designation R-600a in domestic and commercial refrigerators and freezers. In the chemical industry, isobutane is a feedstock for the production of isobutene (isobutylene) and other derivatives.

Properties and safety

Isobutane is highly flammable and should be stored away from heat sources and oxidizers. It is miscible with many organic solvents but insoluble in water. Exposure in high concentrations can pose fire and health hazards, and appropriate handling and ventilation are essential in occupational settings.