Chemical reactions can be classified as either heterogeneous or homogeneous. Which of the following equations below is best classified as a heterogeneous reaction?
(A)2C2H2(g) + 5O2(g) → 4CO2(g) + 2H2O(g) (B)2SO2(aq) + O2(g) → 2SO3(g) (C)C2H2(g) + 5N2O(g) → CO2(g) + H2O(g) + 5N2(g) (D)C(s) + H2O(g) → H2(g) + CO(g)
D