How to calculate density with mL?

The car gets 20.4km/L. If density of octane is .703g/mL calculate how many kilometers the car can travel on 1kg of gas?

• 1) The average mileage rating of the car is 48.0mpg. Convert this into units of kilometers traveled per liter of gasoline consumed. 2) Only using the density of octane .703g/mL, use result from question 1 to calculate how many kilometers the car can travel on one kilogram of gasoline. 3) The chemical formula for octane is C8H18. Using this formula, write a balanced equation for the combustion of octane. 4) Using the mass-to-moles-to-moles-to-mass process and the balanced question from #3 determine how many grams of CO2 is produced for every 1000 grams of octane combusted. 5) Using the quantity of CO2 produced in #4 and the kilometer distance traveled from #2, calculate the grams of CO2 generated by the car for every kilometer traveled.

• Answer:

  1) 48.0 mpg = 48 miles per gallon 1 mile = 1.602 kilometers and one gallon is 3.785 litres So in kilometers per litre the value is 48 * 1.602/ 3.785 = 20.32 km/L 2)Density 0.703g/mL so in 1 kilogram we have 1000 grams Volume = mass/density = 1000/0.703 = 1422.5 ml or 1.4225 L as it travels 20.32 km/L it would travel 20.32 * 1.4225 = 28.9 kilometer So it travels 28.9 km/ 1 kg of fuel. 3) Combustion is nothing , but burning of fuel is presence of oxygen. So the unbalanced equation is, C8H18 + O2 = CO2 + H2O Balancing both sides we get, 2C8H18 + 25O2 = 16CO2 + 18H2O 4)Calculating the mass of octane we have 2 moles of octane produces 16 moles of CO2 2 moles of octane weigh 2(12x8 + 1 x 18) = 2*(96+18) = 2* 114 = 228 grams 16 moles of CO2 = 16(12+2X16) = 16*44 = 704 grams So 228 grams of Octane produce 704 grams of CO2 So 1000 grams of Octane produce (704/228)*1000= 3087.72 grams of CO2 5) 1 gram of Octane produces 3.087 grams of CO2 20.32 is the kilometer travelled / 1000 gram of Octane for for every kilometer travelled, the octane consumed is, 1000/20.32 = 49.21 grams / kilometer So the amount of CO2 produced is 49.21 * 3.087 = 151.92 grams. That completes all the 5 steps.Let me know if you face any problem understanding any part.