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Question
For a certain reaction ΔH° = 219 kJ and ΔS° = –21 J/K. Determine whether the reaction is spontaneous or nonspontaneous.
Solution
Given:
∆H0 = 219kJ; ∆S0 = -21 J/K, ∆G0 = ?
For the standard state, T = 298 K
∆G0 = ∆H0 - T∆S0
= 219 - 298 × (-21) × 10-3
= 219 + 6.258
= 225.3 kJ
Since ∆S < 0 and ∆G0 > 0, the reaction is non-spontaneous.
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