Originally Posted by
Andy_RR
Therein is your error. Gasoline (and I presume similarly, AVGAS) is about 87% Carbon, by mass Most of the rest of the atoms are Hydrogen, which don't weigh nearly as much, despite being more numerous!
0.72kg at 87% = 0.63kg of C, which, multiplying by 44/12, converts to 2.3kg of CO2
Looking at another way... Assume it's octane
C8H18 + 12.5 O2 -> 8 CO2 + 9 H2O
C8H18 has mass 114
8 CO2 has mass 356
So that's 3.1 kg of CO2 per kg of AvGas or 2.3 kg/litre.
Catalysts make CO2, Engines make VOC's, NOx, CO, water and hydrocarbons, ergo we're low carbon.
We've already established that the chief combustion product is CO2. But just before everyone goes off and tries to make CO by incomplete combustion thinking they're doing the world a favour, just bear in mind that the CO will oxidise to CO2 in the atmosphere over a few months anyway.