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Question
Answer the following question.
Determine whether the following reaction is spontaneous under standard state conditions.
2H2O(l) + O2(g) → 2H2O2(l)
if ΔH° = 196 kJ, ΔS° = –126 J/K, does it have a cross-over temperature?
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Solution
When ∆H positive and ∆S is negative, then ∆G is positive regardless of temperature. Hence, the reaction is nonspontaneous at all temperatures. It does NOT have a cross-over temperature.
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