Answer to Question #346584 in General Chemistry for Mayo

Question

PROBLEM: At 25°C (298 K), the reduction of copper(I) oxide is nonspontaneous AG = 8.9 kJ). Calculate the temperature at which the reaction becomes spontaneous. ΔΗ = 58.1 kJ AS = 0.165 kJ/K

Answer 1

The reaction must be ∆G <0 for it to occur spontaneously. When ∆G = 0, the reaction is in equilibrium. therefore, assuming ∆G = 0, we find T:

∆G = ∆H - T * ∆S

T = (∆H - ∆G) / ∆S

T = (58,1 - 0 ) / 0,165

T = 352,12 K

that is, when T = 352.12, the reaction is in equilibrium. and at T> 352.12, the reaction proceeds spontaneously

ANSWER: T> 352,12 K