Final answer:
The two main hydrocarbons in natural gas are methane and ethane, with methane being the primary component. These hydrocarbons are critical in energy supply, with natural gas meeting significant energy needs globally and notably in the United States.
Step-by-step explanation:
The two main hydrocarbons that form natural gas are methane (CH4) and ethane (C2H6). Natural gas is predominantly methane, usually comprising 70-90% of its composition, and serves as a crucial fuel and a potent greenhouse gas. Ethane is the second most abundant component. These hydrocarbons can be found in varying concentrations in both 'wet' and 'dry' natural gas, where 'dry' primarily consists of methane, and 'wet' contains a larger proportion of heavier hydrocarbons like ethane, propane, and butane. These compounds are separated and processed to satisfy different energy needs, such as heating and electricity generation.
Natural gas is also a by-product of oil formation, arising from the degradation of organic matter in sedimentary rocks, and is extracted from the Earth together with petroleum and coal deposits. Its extraction and processing contribute significantly to the energy supply, meeting 20% of world energy needs and 25% of the United States needs.