To burn a gallon of gas, how many grams of oxygen do you need?

Question

I need steps on how to do it and the actual answer because I am a beginner to chemistry . I know the balanced formula, I just dont know how to take it farther and find the grams of oxygen.

2C812 + 25O2 ---> 16CO2 + 18H2O is the balanced equation.

Thank you very much!!

Note: A step by step answer would be amazingly awesome because I am terrible at chemistry!

Answer 1

well, its all in the stoichiometry.
since u have the balanced equation, just do it out!
use 1 gall C8H12 * the equavalent in liters (convert 1 gallon to liters) and then u can do the stoichiometry going from liters of C8H12 to grams of oxygen using the molar ratio.
good luck! hope this helps!

Answer 2

First off, your formula for octane (one of the major components of gasoline) is wrong, even though the equation is balanced correctly. Octane is C8H18, not C8H12.

You need the density of gasoline, because you need to use these steps:

1. Convert gallons of gasoline to liters (1 gallon = 3.785 L).
2. Convert liters of gasoline to grams (multiply by the density).
3. Convert grams of gasoline to moles (divide by the molecular weight, which is 114 for C8H18).
4. Convert moles of gasoline burned to moles of oxygen needed (multiply by 25/2, which is the stoichiometric ratio from the balanced equation).
5. Convert moles of oxygen to grams of oxygen (multiply by the molecular weight, which is 32 for O2).

I'd give you the number, but I don't have the density of gasoline memorized.