A reaction has a positive ΔH and a postiive ΔS. When is the reaction spontaneous (if ever)?   ΔG = ΔH - TΔS     High temperature     Low temperature     Always     Never

Would the following reaction be expected to have a positive or negative entropy change?N2(g)   +   3H2(g)   ---------->   2NH3(g)

eq M M IS M ots M M M # 3 E D Consider the reaction 2H₂O(l) 2H₂(g) + O₂(g) The standard free energy change for this reaction is 474.2 kJ. The free energy change when 1.88 moles of H₂O(1) react at standard condition is kJ. 20 C What is the maximum amount of useful work that the reaction of 1.88 moles of H₂O(l) is capable of producing in the surroundings under standard conditions? If no work can be done, enter none. kJ Submit Answer $ 4 R F > % 5 T [References] Use the References to access important values if needed for this question. Retry Entire Group 9 more group attempts remaining G Cengage Learning Cengage Technical Support 6 B MacBook Pro Y Topics] H & 7 N U J ▶II * 00 8 M I ( 9 K. O < 96 ) L P V t Previous Email Instructor Save and Exit { + 11 [ Next ? } 1 dele

Which of the following processes are spontaneous.  Cold water warming to room temperature Sorting names alphabetically Black hair turning grey Wind scattering leaves in a pile Shoveling snow Removing stain from a cloth Sublimation of naphthalene at room temperature

Determine whether the following reactions are spontaneous or non-spontaneous. a) N2 (g) + 3 H2 (g) ⟶ 2 NH3 (g), ΔG = -32,960 J b) 2 NH3 (g) ⟶ N2 (g) + 3 H2 (g), ΔG = 32,960 J HINT: The change in free energy (ΔG) for reaction is equal to the difference in free energy between the products (Gproducts) and the reactants (Greactants): ΔG = (Gproducts) - (Greactants) In spontaneous reactions, the free energy of the products (Gproducts) of a reaction is less than the free energy of the reactants (Greactants). When this is the case, will the change in free energy (ΔG) will have a negative value or a positive value?

Calculate ΔS when 25.0 g ethanol at 50.0 °C is added to 75.0 g ethanol at 10.0 °C in an insulated container where Cp = 111.5 J/mol K. Calculate the change in entropy of each ethanol sample, and then the total entropy change. Comment on what is happening to each sample, and overall. (answers: warm = -6.11 J/K; cold = +5.69 J/K; total = 0.42 J/K)

When nickel sulfide is burned in oxygen its oxide and sulfur dioxide are formed: 2NiS(s) + 3O2 (g) --> 2SO2 (g) + 2NiO (s) Calculate the value of ΔS at 25oC. So for NiS(s) is 53 J mol-1K-1, and NiO(s) is 37.99 J mol-1K-1.

For the following reaction, ΔH° is 47.7 kJ/mol and ΔS° is 81.8 J/mol*K. At what temperature in K will the reaction become spontaneous? A2D(g) + C3(g) → 2AC(g) + DC(g)

1. For which of the following processes would ΔS° be expected to be most positive? Group of answer choices A. H2O(l) → H2O(s) B. 2NO2(g) → N2O4(g) C. NH3(g) + HCl(g) → NH4Cl(s) D.O2(g) + 2H2(g) → 2H2O(g) E. 2N2H4(g) → 2NH3(g) + N2(g) + H2(g) F. O2(g) + 2H2(g) → 2H2O(g)   2. For the process HX(s) → HX(l), ΔH° = 9.17 kJ/mol and ΔS° = 43.9 J/mol/K. What is the melting point of HX? ΔΔ G = ΔΔ H - T ΔΔ S Group of answer choices A. –130 °C B. 130 °C C. 209 °C D. 64 °C E. –64 °C   3. Substance X has a heat of vaporization of 45.1 kJ/mol at its normal boiling point (423°C). For the process X(l) → X(g) at 1 atm and 423°C calculate the value of ΔSsurr. ΔΔSsurroundings = -ΔΔHsystem/T Group of answer choices A. –64.8 J/K mol B. –107 J/K mol C. 0 D. 107 J/K mol E. 64.8 J/K mol

Calculate ΔGo in kJ for the following chemical reaction at 60oC, given the ΔHf values below, and given that the change in entropy for the reaction is EITHER (i.e. you have to choose which) positive or negative 284.5 J/mol K. NH4Cl (s)   <-->   NH3 (g)   +   HCl (g)   -314                    -45              -92      (kJ/mol)