Question

How much CO2 ir released (in pounds) per year of your normal driving? comment on the size of your answer. CO2 is a greenhouse gas) how cound you reduce "carbon footprint'.

- Assume gasoline is mostly octane

- how many miles do you drive per week or per month

- how many miles per year?

- Gas mileage of your car> (# miles per gallon of gas)

- stoichiometry of the reaction

Answer 1

Ans. a. Average driving per month = 60 miles

b. Average driving per year = 12 months x 60 miles                     [1 year = 12 months]

                                    = 720 miles

c. Gas mileage of my car = 28.30 miles per gallon

            Total gasoline used in 1 year = total driving in 1 year / Average mileage of car

                                                = 720 miles/ (28.30 miles / gallon) = 25.44 gallon

d. Stoichiometry of reaction:       C₈H₁₈ + (25/2) O₂ -----------> 8CO₂ + 9 H₂O

molecular mass of gasoline (C₈H₁₈) = 114.23 gram/ mol

molecular mass of CO₂ = 44.00 g /mol

Total mass of CO2 produced from 1 mol octane = 8 moles CO2 x molar mass of 1 CO2

                                                = 8 mol x 44.00 g /mol = 352 gram

From the stoichiometry of reaction, 114.28 g (= 1 mol octane) produces 352.0 g CO₂.

Or, 114.28 kg octane produces 352.0 kg CO₂ (mass converted to kg).

Density of gasoline = 0.702 kg/ L                                           [1 L = 0.264172 gallon]

                                    = 0.702 kg/ (0.264172 gallon) = 2.66 kg/ gallon

Total mass of gasoline required in 1 year

= volume of gasoline required in 1 year x density of gasoline

                                    = 25.44 gallon x (2.66 kg/ gallon) = 67.67 kg

Now, we have 114.28 kg octane produces 352.0 kg CO₂- stoichiometry of reaction.

So, mass of CO2 produced from 67.67 kg gasoline (CO₂ produced per year)

                                                = (352.0 kg CO₂ / 114.28 kg octane) x 67.67 kg octane

                                                = 208.43 kg CO₂

                                                = 459.52 lb CO₂                     [1 kg = 2.20462 lb]