For a reaction in which ΔH = 125 kJ and ΔS = 325 J/K, determine the temperature in Celsius above which the reaction is spontaneous.

The reaction between hydrogen gas and carbon to produce the gas known as ethylene is:2 H2(g) + 2 C(s) → H2C=CH2(g), ∆G = +16.3 kcal/mol (+68 kJ/mol) 25 °C.Is this reaction spontaneous at 25 °C?

The change of state from liquid H2O to gaseous H2O has ∆H = +9.72 kcal/mol(+40.7 kJ/mol) and ∆S = -26.1 cal/(mol • K) [-109 J/(mol •K)].Is the change from liquid to gaseous H2O favored or unfavored by ∆H? By ∆S?

The change of state from liquid H2O to gaseous H2O has ∆H = +9.72 kcal/mol(+40.7 kJ/mol) and ∆S = -26.1 cal/(mol • K) [-109 J/(mol •K)].What are the values of ∆H and ∆S (in kcal/mol and kJ/mol) for the change from gaseous to liquid H2O?

Two curves are shown in the following energy diagram: Which curve represents the spontaneous reaction, and which the nonspontaneous?

The following diagram portrays a reaction of the type A(s) → B(g) + C(g), where the different-colored spheres represent different molecular structures. Assume that the reaction has ∆H = +9.1 kcal/mol (+38.1 kJ/mol).

Is the reaction likely to be spontaneous at all temperatures, nonspontaneous at all temperatures, or spontaneous at some but nonspontaneous at others?