Ethanol, C2H5OH, is mixed with gasoline and sold as gasohol. Use the following to calculate the grams of ethanol needed to provide 367 kJ of heat.

Question

C2H5OH(l) + 3 O2(g) �¨ 2 CO2(g) + 3 H2O(g)
ƒ¢H = −1235 kJ

Answer 1

I suppose that funny symbolism is delta H.
So 1235 kJ heat are released when 1 mol(46 grams) C2H5OH are combusted. YOu want 367 kJ; therefore,
46 grams x (367 kJ/1235 kJ) = ? grams.

Answer 2

21