CS2(l) + 4H2(g) CH4(g) + 2H2S(g) This reaction occur spontaneously as written when all reactants and products are in their standard states ? (T = 298.17 K) What is G° for this reaction in J/mol?

Thermodynamics provides a way to interpret everyday occurrences. If you live in northern climates, one common experience is that during early winter, snow falls but then melts when it hits the ground. Both the formation and the melting happen spontaneously. How can thermodynamics explain both of these seemingly opposed events?

For the reaction at 298 K, 2NO2(g)N2O4(g) the values of H and S are 58.03 kJ and 176.6 J/K, respectively. What is the value of G at 298 K? Assuming that H and S do not depend on temperature, at what temperature is G = 0? Is G negative above or below this temperature?

For the reaction C2H2(g)+4F2(g)2CF4(g)+H2(g) S is equal to 358 J/K. Use this value and data from Appendix 4 to calculate the value of S for CF4(g).

For the reaction BaCO3(s) BaO(s) + CO2(g), rG = +219.7 kJ/mol-rxn. Using this value and other data available in Appendix L, calculate the value of fG for BaCO3(s).

9.83 A student performing a calorimetry experiment combined 100.0 mL of 0.50 M HCl and 100.0 mL of 0.50 M NaOH in a coffee cup calorimeter. Both solutions were initially at 20.0°C, but when the two were mixed, the temperature rose to 23.2°C. (a) Suppose the experiment is repeated in the same calorimeter but this time using 200 mL of 0.50 M HCl and 200.0 mL of 0.50 M NaOH. Will the T observed he greater than, less than, or equal to that in the first experiment, and why? (b) Suppose that the experiment is repeated once again in the same calorimeter, this time using 100 mL of 1.00 M HCl and 100.0 mL of 1.00 M NaOH. Will the T observed he greater than, less than, or equal to that in the first experiment, and why?

Determine whether each of the following statements is true or false. (a) An exothermic reaction is spontaneous. (b) When G° is positive, the reaction cannot occur under any conditions. (c) S° is positive for a reaction in which there is an increase in the number of moles. d) If H° and S° are both negative, G° will be negative.

How is the sign of q, heat, defined? How does it relate to the total energy of the system?

Nickel metal reacts with carbon monoxide to form tetra-carbonyl nickel, Ni(CO)4: Ni(s)+4CO(g)Ni(CO)4(g) This reaction is exploited in the Mond process in order to separate pure nickel from other metals. The reaction above separates nickel from impurities by dissolving it into the gas phase. Conditions are then changed so that the reaction runs in the opposite direction to recover the purified metal. (a) Predict the sign of S for the reaction as written above. (b) Use tabulated thermodynamic data to calculate H, S , and G for the reaction. (c) Find the range of temperatures at which this reaction is spontaneous in the forward direction.

Given the following data 2O3(g) 3O2(g)H = 427 kJ O2(g) 2O(g)H = 495 kJ NO(g) + O3(g) NO2(g) + O2(g)H = 199 kJ Calculate H for the reaction NO(g) + O(g) NO2(g)