Answer:- 88.0 kg of carbon dioxide.
Solution:- Distance and car mileage are given from which we could calculate the fuel required to cover the given distance. With the help of the given fuel density and fuel calculated volume the mass of fuel that is octane could be calculated. Some unit conversions are also done here. After this by writing balanced combustion equation and using stoichiometry the amount of carbon dioxide produced could easily be calculated.
The calculations are shown below:
[tex]235mile(\frac{1gallon}{21.5mile})(\frac{3.785L}{1gallon})(\frac{1000mL}{1L})(\frac{0.69gram}{1mL})[/tex]
= 28545.94 g of octane
The balanced equation for the combustion of Octane is:
[tex]2C_8H_1_8+25O_2\rightarrow 16CO_2+18H_2O[/tex]
We will use dimensional analysis here also to solve for mass of carbon dioxide formed. Grams of octane are converted to moles and then using mole ratio the moles of carbon dioxide are calculated. Moles are converted to grams on multiplying by molar mass and then finally the grams are converted to kilograms as:
[tex]28545.94gC_8H_1_8(\frac{1moleC_8H_1_8}{114.23gC_8H_1_8})(\frac{16moleCO_2}{2moleC_8H_1_8})(\frac{44gCO_2}{1moleCO_2})(\frac{1kg}{1000g})[/tex]
= [tex]88.0kgCO_2[/tex]
So, 88.0 kg of carbon dioxide would be produced by an automobile.