Climate Change Chemistry

Long before the recent events, I understood the science behind global climate change. We are creating a manmade disaster by continuing to burn fossil fuels. Call it the dinosaurs’ revenge, even though fossil fuels trace their origin to tiny organisms.

Carbon is the common element in fossil fuels. When fossil fuels are burned, they produce carbon dioxide gas and water. Both carbon dioxide and water are greenhouse gases.

 So put on your science hats for a little basic chemistry.

The carbon atoms [C] combine with oxygen [O₂] to produce carbon dioxide [CO₂].

For example,

Coal                                                                     C + O₂ → CO₂

Natural Gas (Methane)                            CH₄  2O₂ → CO₂ + 2H₂O

Gasoline (Ethanol)                                     C₂H₅OH + 3O₂ → 2CO₂ + 3H₂O

The numbers in front of the molecules of oxygen, carbon dioxide, and water are used to make sure there are an equal number of carbon, oxygen, and hydrogen atoms on both sides of the chemical reaction. Another way of looking at the chemistry is to note that burning a single molecule of ethanol (gasoline) produces three times the amount of carbon dioxide as burning coal.

Carbon dioxide is a greenhouse gas that creates a blanket in the atmosphere to hold in heat.

According to Wikipedia, greenhouse gases are the gases in the atmosphere that trap heat, raising the surface temperature of Earth. Unlike other gases, greenhouse gases absorb the radiation that the Earth emits, resulting in the greenhouse effect. The Earth is warmed by sunlight, causing its surface to radiate heat, which is then mostly absorbed by greenhouse gases. Without greenhouse gases in the atmosphere, the average temperature of Earth’s surface would be about 0°F rather than the present average of 59°F.

The five most abundant greenhouse gases in Earth’s atmosphere, listed in decreasing order of presence, are: water vapor, carbon dioxide, methane, nitrous oxide, and ozone.  Water vapor causes about half of the greenhouse effect. [1]

Burning natural gas to heat your home and using gasoline to fuel your car or truck will produce water vapor as shown in the above equations. Gasoline combustion produces twice as much water as does burning natural gas.

[1] “Greenhouse gas,” Wikipedia, Greenhouse gas – Wikipedia