Answer:
Using the standard heats of formation below, what is the heat of reaction when sulfur dioxide reacts with oxygen to form sulfur trioxide? 2SO2(g) + O2(g) → 2SO3(g) ∆Hf° SO2(g) = –298.8 kJ/mol ∆Hf° SO3(g) = –395.7 kJ/mol –193.8 kJ –201.9 kJ –492.6 kJ –694.5 kJ.
Explanation:
To calculate the heat of reaction we need to subtract the summ of all reagent's formation heat from the summ of all product's formation heat.
For this example it will be:
2*Hf(SO3) - ( 2*Hf(SO2) + Hf(O2) ) =
2 * (-395.7) - ( 2 * (-298.8) + 1 * 0) =
-791.4 + 597.6 = - 193.8
