A. Calculate the standard enthalpy change of the reaction in kJ. Is the process endothermic or exothermic! B. Calculate the standard entropy change of the reaction in J/K. C. Calculate the standard Gibbs free energy change of the reaction in kJ at 298 K. Is the reaction spontaneous at 298 K? ( s)

4. The standard free energy (AG°) for a reaction at 298 K is -104 J / mol. What is Keq for this reaction?

33. Use the standard free energy of formation data in Appendix G to determine the free energy change for each of the following reactions, which are run under standard state conditions and 25 °C. Identify each as either spontaneous or nonspontaneous at these conditions. MnO2 (s) ⟶ Mn(s) + O2 (g) H2 (g) + Br2 (l) ⟶ 2HBr(g) Cu(s) + S(g) ⟶ CuS(s) 2LiOH(s) + CO2 (g) ⟶ Li2CO3 (s) + H2O(g) CH4 (g) + O2 (g) ⟶ C(s, graphite) + 2H2O(g) CS2 (g) + 3Cl2 (g) ⟶ CCl4(g) + S2Cl2 (g)

For a given reaction, ΔH = +35.5 kJ/mol and ΔS = +83.6 J/mol·K. Which of the following is TRUE? a. The reaction is spontaneous at standard conditions. b. The reaction is spontaneous at T > 425 K. c. The reaction is spontaneous at all temperatures. d. The reaction is spontaneous at T < 425 K.

Use standard thermodynamic data to calculate G at 298.15 K for the following reaction, assuming that all gases have a pressure of 20.46 mm Hg.2NO(g) + O2(g)2NO2(g)  G =  ______kJ/mol

The following reaction is endothermic. 2NH3(g) → N2(g) + 3H2(g) This means the reaction   A. will be spontaneous at high temperatures. B. will be spontaneous at low temperatures. C. is not spontaneous at any temperature. D. is spontaneous at all temperatures.

49.For the decomposition of hydrogen peroxide to water and oxygen,         H2O2(g) ⟶⟶ H2O(g) + O2(g) ΔΔH° = -106 kJ, and ΔΔS° = +0.0580 kJ/K. In what temperature range is the reaction spontaneous (ΔΔG° < 0)? A. The temperature must be greater than 1.83××103 K B. The temperature must be less than 1.83 ××103 K. C. The temperature must be between 225 K and 1.83 ××103 K. D. ΔΔG° is always less than zero. E. ΔΔG° is never less than zero.

Consider the two reactions below, resulting in the formation of hydrazine a. Reaction A: 2 NH3 (g) =N2H4 (I) + H2 (g) Reaction B: N2 (g) +2 H2 (g) =N2H4 (1) i. Calculate AGxn at 25.0 °C for each reaction ii. Calculate Keg for each reaction at 25.0 °C iii. State whether each reaction is spontaneous or non-spontaneous at 25.0 °C iv. At what temperature, if any, does each reaction transition between spontaneous and non-spontaneous? v. Which of these reactions, if either, would be desirable for the industrial synthesis of hydrazine? Explain.

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