Answer to Question #110812 in General Chemistry for Philip

Question

A certain hydrocarbon on complete combustion at s.t.p produced 89.6dm3 of CO2 and 54g of water. The hydrocarbon should be

A. C6H6
B. C4H10
C. C5H10
D. C4H6

Please show working

Answer 1

C_xH_y + O2 = xCO₂ + y/2 H₂O

If we burn 1 mol of certain hydrocarbon, we would get x mol of CO₂ and y/2 mol of H₂O.

During combustion, we received 54/18 = 3 mol of water and 89.6/22.4 = 4 mol CO₂.

The hydrocarbon should be C₄H₆ (option D).