posted by sari .
What mass of CO2, a greenhouse gas, is produced per liter of each fuel (assuming complete combustion)
I got this data
density of ethanol = 0.785 g/mL
density of octane = 0.699 g/mL
Ethanol) C2 H5 OH + 2O2 -> 2CO2 + 3H2O
delta H combustion ethanol = -1234.8 Kj/mol
Octane) C8H18 + (25/2)O2 -> 8CO2 + 9H2O\
delta H combustion = -5074.3 KJ/mol
Figure the liters of CO2 due to ethanol, well you get as you stated, two moles of co2 for each mole of ethanol, so ..
so figure that out, then twice that is the moles of CO2, and figure about 24liters /mole
Now do the same technique for the nine liters of octane.