What is the standard enthalpy change for the following reaction?
3CH₄(g) + 4O₃(g) → 3CO₂(g) + 6H₂O(g)
Substance
ΔH°_f (kJ/mol)
CH₄(g)
-74) 87
O₃(g)
+142.7
CO₂(g)
-393.5
H₂O(g)
-241.8

Question

What is the standard enthalpy change for the following reaction? 3CH₄(g)+ 4O₃(g)→ 3CO₂(g)+ 6H₂O(g) Substance ΔH°_f (kJ/mol) CH₄(g) -74)87 O₃(g) +142.7 CO₂(g) -393.5 H₂O(g) -241.8

Quizplus · Accepted Answer

To calculate the enthalpy change of the reaction we need to subtract the sum of the enthalpies of the reactants from the sum of the enthalpies of the products:
(3 mol x ΔH°f(COS) + 6 mol x ΔH°f(H2SO4)) - (3 mol x ΔH°f(CH4) + 4 mol x ΔH°f(O2)) = -2977.5 kJ. Therefore, the correct answer is B.

What Is the Standard Enthalpy Change for the Following Reaction