Natural gas is a fossil fuel that is widely used in the U.S. for heating, cooking, and electricity generation, and it is also used as a chemical feedstock for the manufacture of plastics and other products. But because it consists primarily of the greenhouse gas methane, natural gas is one of the leading sources of methane emissions. Natural gas is a fossil fuel that is widely used in the U.S. for heating, cooking, and electricity generation, and it is also used as a chemical feedstock for the manufacture of plastics and other products. But because it consists primarily of the greenhouse gas methane, natural gas is one of the leading sources of methane emissions. Analytical Chemistry Materials Science Phys.org – latest science and technology news stories