For the reaction 2 C4H10 (g) + 13 O2 (g) → 8 CO2 (g) + 10 H2O (g) AH° is-125 kJ/mol and AS is +253 J/K - mol. This reaction is A. spontaneous at all temperatures B. spontaneous only at high temperature C. spontaneous only at low temperature D. nonspontaneous at all temperatures E. unable to determine without more information

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.

The following reaction takes place at 120°C: H20( I) → H20( g) AH 44.0 kJ/ mol AS = 0.119 kJ/mol K Which of the following must be true? O a. The reaction is not spontaneous. b. The reaction is spontaneous. O c. AG = 0 O d. AG <0 O e. Two of these.

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.

If the process is exothermic and not spontaneous, then what must be TRUE? O a. AS0 O c. AH=0 O d. AS> 0

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3. Determine the temperature (°C) range, in which the following reaction will become spontaneous. (temperatures greater, less than or equal to the given value) Fe2O3(s) + 2Al(s) → 2Fe(s) + Al203(s) AHxn = -851.5 kJ/mol ASpen = -375.2 J/mol K %3D