Chapter 13, Problem 15P

Billions of pounds of acetic acid are made each year, much of it by the reaction of methanol with carbon monoxide. (AssumeT= 298 K.) CH3OH() + CO(g) CH3COOH() (a) By calculating the standard Gibbs free energy change, rG, for this reaction, show that it is product-favored. (b) Determine the standard Gibbs free energy change, rG,for the reaction of acetic acid with oxygen to form gaseous carbon dioxide and liquid water. (c) Based on this result, is acetic acid thermodynamicallystable compared with CO2(g) and H2O()? (d) Is acetic acid kinetically stable compared with CO2(g)and H2O()?

Use data from Appendix D to calculate the standardentropy change at 25°C for the reaction CH3COOH(g)+NH3(g)CH3NH2(g)+CO2(g)+H2(g) Suppose that 1.00 mol each of solid acetamide, CH3CONH2(s), and water, H2O(l), react to give thesame products. Will the standard entropy change belarger or smaller than that calculated for the reactionin part (a)?

Enthalpy changes often help predict whether or not a process will be spontaneous. What type of reaction is more likely to be spontaneous: an exothermic or an endothermic one? Provide two examples that support your assertion and one counterexample.

Appendix J lists standard molar entropies S, not standard entropies of formation rS. Why is this possible forentropy but not for internal energy, enthalpy, or Gibbsfree energy?

Solid NH4NO3 is placed in a beaker containing water at 25 C. When the solid has completely dissolved, the temperature of the solution is 23.5 C. (a) Was the process exothermic or endothermic? (b) Was the process spontaneous? (c) Did the entropy of the system increase? (d) Did the entropy of the universe increase?

What are the two ways that a final chemical state of a system can be more probable than its initial state?

The standard molar entropy of methanol vapor, CH3OH(g), is 239.8 J K1 mol-1. (a) Calculate the entropy change for the vaporization of 1 mol methanol (use data from Table 16.1 or Appendix J). (b) Calculate the enthalpy of vaporization of methanol, assuming that rS doesnt depend on temperature and taking the boiling point of methanol to be 64.6C.

The formation of aluminum oxide from its elements is highly exothermic. If 2.70 g Al metal is burned in pure O2 to give A12O3, calculate how much thermal energy is evolved in the process (at constant pressure).

For one day, keep a log of all the activities you undertake that consume Gibbs free energy. Distinguish betweenGibbs free energy provided by nutrient metabolism andthat provided by other energy resources.