Chemistry
posted by M .
Octane has a density of 0.692 at 20degree C . How many grams of O2 are required to burn 17.0gal of C8H18 ?
Stepbystep explanation much appreciated with as much detail as possible so I can understand. Thanks!

0.692 what? g/mL?
2C8H18 + 25O2 ==> 16CO2 + 18H2O
Convert 17.0 gallons octane to L, then to mL.
Use density (in g/mL?) to convert mL octane to grams octane.
Convert grams octane to mols. mols = grams/molar mass
Use the coefficients in the balanced equation to convert mols octane to mols O2.
Now convert mols O2 to grams. g = mols x molar mass. 
jk

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