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Using the following bond dissociation data, determine the enthalpy change for the conversion 8S(s) + 3/2 S₈(g): H₂S(g) → 2H(g) + S(g), ΔH = 239.0 kcal mol⁻¹ H₂S(g) → 2H(g) + S(g), ΔH = 175.0 kcal mol⁻¹
- +512.0 kcal
- -512.0 kcal
- 508.0 kcal
- -508.0 kcal
Correct answer: -508.0 kcal
Solution
The correct option is -508.0 kcal because the enthalpy change for the reaction is calculated by considering the bond dissociation energies and the stoichiometry of the reaction, leading to a net release of energy when converting solid sulfur to gaseous sulfur.
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