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The variation of equilibrium constant with temperature is given below : Temperature Equilibrium Constant T1 = 25°C K1 = 100 T2 = 100°C K2 = 100 The values of ΔH° , ΔG° at T1 and ΔG° at T2 (in kJ mol−1) respectively, are close to [use R = 8.314 JK−1 mol−1]
- 28.4, −7.14 and −5.71
- 0.64, −7.14 and −5.71
- 0.64, −5.71 and −14.29
- 28.4, −5.71 and −14.29
Correct answer: 0.64, −7.14 and −5.71
Solution
The correct option reflects that the equilibrium constant remains constant despite the change in temperature, indicating that the reaction is nearly thermoneutral, leading to a small ΔH° value. Consequently, the Gibbs free energy change (ΔG°) at both temperatures is calculated using the equilibrium constant, resulting in the specified values.
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