What hydrocarbon makes up most of natural gas?

Methane makes up most of natural gas. It is the simplest alkane, consisting of one carbon atom bonded to four hydrogen atoms, with the chemical formula CH₄.

Natural gas from underground reservoirs commonly contains methane alongside smaller quantities of ethane, propane, butane, carbon dioxide, nitrogen, and water vapor. Processing plants remove many of these impurities before the gas enters distribution networks.

Methane is colorless and odorless in its pure form. Gas suppliers add odorants, usually sulfur-containing compounds, so leaks can be detected more easily. Burning methane produces mainly carbon dioxide and water when combustion is complete.

Methane is also a potent greenhouse gas when released unburned. It can come from oil and gas operations, coal mines, landfills, wetlands, agriculture, and other sources. Ethane and propane are important natural-gas components, but methane is the dominant one and is the principal fuel delivered through gas pipelines.