
Frank M. answered 06/20/20
Affordable, Quality tutoring in Chemistry and Algebra
This is a combustion reaction. The products of combustion are CO2 + H2O. You must first balance thje reaction: C8H18 + O2 ---> CO2 + H2O. C8H18 + 25/2 O2 ---> 8CO2 + 9H2O, multiply the entire equation by 2 to clear the 1/2 in the denominator of the O2, and you get 2C8H18 + 25O2---> 16CO2 + 18H2O. Now the equation is balanced so convert 14 grams of octane to moles, 14grams/114 grams/mole, and you have 0.8421 moles of octane. 0.8421 moles octane x 25 moles O2/2 moles octane(from the balanced equation) =10.52 moles O2=10.52 moles x 32 grams O2/mole=336.84 grams O2.