Why do carbon dioxide emissions weigh more than the original fuel?

During complete combustion, each carbon atom in the fuel combines with two oxygen atoms in the air to make carbon dioxide. The addition of two oxygen atoms to each carbon atom forms carbon dioxide, which has an atomic weight of 44 — roughly 3.6667 times the atomic weight of the carbon (12).

For example, subbituminous coal is on average 51% carbon, so the carbon in a short ton (2,000 pounds) weighs 1,020 pounds. The carbon dioxide emissions from burning a short ton of subbituminous coal are approximately 3,740 pounds, or about 3.67 times the weight of the carbon in a short ton of coal, and 1.87 times the weight of a short ton of coal.

The periodic table of elements shows the atomic weights of all elements.

How much carbon dioxide (CO2) is produced when different fuels are burned?

Last reviewed: June 19, 2012

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