Calculating a gallon of gasoline into pounds of C02 is often quite confusing. Luckily smoo did some number crunching in simple terms to explain it.

I get a lot of questions like this: “Can burning 1 gallon of gasoline really release almost 20 pounds of carbon dioxide (CO2)? That does not make sense. Does the carbon dioxide really weigh 20 pounds? Can you weigh it? How can this be true?”

First of all, yes, this is true.

My genius PhD chemist friend Maria promised to share with me the calculations that demonstrate how this works. I am going to share these with you and then explain them in simple English so your head does not explode (unless you are an AP Chemistry student in high school and then you might want to calculate the numbers yourself JUST FOR FUN). From Maria (note that a “Mole”, abbreviated as mol, is a unit of molecular measurement):

Here is a calculation that I did for gasoline…

Answer:

Energy Information Administration (EIA) stated that 1 gal (3.78 L) of gasoline (density = 0.70 g/mL and approximate composition C8H18) gives 8 kg (18 lbs) of CO2.

Combustion of gasoline
C8H18 + (25/2) O2 -> 8CO2 + 9H2O

3.78 L(1000 mL/L)(0.70g/ mL) = 2646 g gasoline
2646 g gasoline(8 mol CO2/ 1 mol gasoline)(1 mol/114 g gasoline) = 185.68 mol CO2
185.68 mol CO2 (44 g/mol CO2) =8,170 g or 8 kg
8,170 g * 0.0022 lb/g = 17.7 lb or 18 lb

The full article is available here

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