In conversion of limestone to lime, CaCO_3(s) → CaO(s) + CO_2(g) , the values of H^0 and S^0 are +179.1 kJ mol^-1 and 160.2 J/K respectively at 298 K - Chemistry MCQ AIEEE 2007 2026 | ExamTest.live

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In conversion of limestone to lime, CaCO_{3} (s) \to CaO (s) + CO_{2} (g), the values of Δ H^{0} and Δ S^{0} are + 179.1 kJ mol^{- 1} and 160.2 J/K respectively at 298 K . Above which temperature will the reaction become spontaneous?

Solution & Step-by-step Explanation

A reaction is spontaneous when Δ G < 0 .The threshold for spontaneity is when Δ G = 0 . Δ G = Δ H - T Δ S = 0 ⟹ T = \frac{Δ H}{Δ S} Convert Δ H to Joules: Δ H = 179.1 \times 1000 = 179100 J mol^{- 1} . T = \frac{179100}{160.2} \approx 1117.97 K For Δ H > 0 and Δ S > 0, the reaction is spontaneous at temperatures above the equilibrium temperature.Thus, T > 1118 K .

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In conversion of limestone to lime, CaCO_{3} (s) \to CaO (s) + CO_{2} (g), the values of Δ H^{0} and Δ S^{0} are + 179.1 kJ mol^{- 1} and 160.2 J/K respectively at 298 K . Above which temperature will the reaction become spontaneous?

1008 K

1200 K

845 K

1118 K

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