Final answer:
Natural gas consists mostly of CH4 (methane) and is a potent greenhouse gas. It is found with petroleum and coal deposits and is released into the atmosphere from various sources. It contributes to methane emissions.
Step-by-step explanation:
Natural gas consists mostly of CH4 (methane). It is primarily composed of methane (CH4) and is a very potent greenhouse gas. It is released into the atmosphere from coal mines, oil and gas wells, and natural gas storage tanks, pipelines, and processing plants.
These leaks are the source of about 25% of total U.S. methane emissions. Natural gas is found with petroleum in reservoir rocks and with coal deposits, and these fossil fuels are extracted together.