Chemistry Problems
Name ____________________________________________________________
A. If I use 2.5 gallons of gasoline (1710 grams) to drive to my parents’ home, how many moles of CO2 will be
exhausted into the atmosphere? What if I used an alternative fuel? Could I reduce my greenhouse gas emissions?
What if my car is NOT tuned up and it now takes 2.7 gallons to drive the same distance. How much more CO2 do
I produce?
B. The ozone molecules in the stratosphere absorb much of the harmful radiation from the sun before it reaches the
Earth. Typical temperature of the stratosphere is 251.0 K while the pressure is low, just 0.00101 atm. How many
ozone molecules are present in 10.00 Liters of air under those conditions??
C. Use the table below to determine how many liters of air must react with 2500. mL of hexane in order for
combustion to occur completely. The percentage of oxygen in air is 20.9%.
Reactants
hexane
oxygen
Formula
C6H14
O2
Molar Mass
86.2 g/mol
32.00 g/mol
Density
0.660 g/mL
1.331 g/L
Volume
2500. mL
?
Mole Ratio
2
19
1.
A truck emits NO2 at a rate of 0.500 g/km. From the equations below, determine how much ozone can be
produced per kilometer of travel by this vehicle.
NO2(g)NO(g) + O(g)
O2(g) + O(g) O3(g)
2.
The owner of a light truck finds that the ozone emissions from his vehicle are 0.600 g/km. Is the amount of NO2
produced by this truck within the allowed Clean Air Act targets for 1996?
NO2(g)NO(g) + O(g)
O2(g) + O(g) O3(g)
Clean Air Act Targets for 1996 Air Pollution*
Pollutant
Cars
Light Trucks
Hydrocarbons
0.25 g/km
0.50 g/km
Carbon Monoxide
2.1 g/km
2.1 –3.1 g/km, depending on truck size
Oxides of nitrogen (NO2)
0.25 g/km
0.25 – 0.68 g/km, depending on truck size
Motorcycles
5.0 g/km
12 g/km
not regulated
*Note: excludes standards for diesel-powered vehicles. EPA standards for cars and light trucks are actually measured in grams per mile at 75 oF.
3.
Acid rain containing H2SO4 is a product of sulfur combustion in gasoline according to the two reactions shown
below. If a sample of gasoline is found to contain 75.0 g of S, how many moles of H2SO4 can be produced in
rain?
S(s) + O2  SO2(g)
2SO2(g) + 2H2O(l) + O2(g) 2H2SO4(aq)
4.
Acid rain can also form from the combustion of nitrogen gas to produce HNO3 in water. If a car burns 425 g of
N2, how many moles of HNO3 can be produced as acid rain?
N2(g) + 2O2(g) 2NO2(g)
3NO2(g) + H2O(l) 2HNO3(aq) + NO(g)