Use Hess's Law to Calculate the Enthalpy Change for the Reaction

question 22

Multiple Choice

Use Hess's Law to calculate the enthalpy change for the reaction WO₃(s) + 3H₂(g) → W(s) + 3H₂O(g)
From the following data:
2W(s) + 3O₂(g) → 2WO₃(s) ΔH = −1685.4 kJ
2H₂(g) + O₂(g) → 2H₂O(g) ΔH = −477.84 kJ

• A)125.9 kJ
• B)252.9 kJ
• C)364.9 kJ
• D)1207.6 kJ
• E)None of these choices are correct.

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