College Chem
posted by D .
How many liters of carbon dioxide at 20 oC and 750 torr are produced when one gallon of toluene is burned?
C7H8 + 9O2 ==> 7CO2 + 4H2O
1 gallon toluene = about 3,785 mL
density = about 0.867 g/mL
mass toluene = 3785 mL x 0.867 g/mL = 3282 grams.
moles toluene = grams/molar mass = 3282/92 = about 36 moles.
From the equation above, 1 mole C7H8 will produce 7 moles CO2; therefore, 36 moles toluene will produce 7 x 36 = about 250 moles CO2..
PV = nRTâ€“ V=250 X 8.314 X 293 / 750 = 812 L

Three errors:
1. When I posted this work about 3 hours ago, you will note I used about several times. You need to go through the math and calculate the individual steps to more precision than that.
2. You used the wrong R. If you use pressure in torr you must use 0.08205 L*atm/mol*K
3. If you intend to use torr, you must convert that to atmospheres. 750 torr = (750/760) atm.
I thin the answer is closer to 6,000 L but check my math on that.