(a)
Interpretation:
The free energy change for the conversion of liquid water to water vapor at 100°C needs to be determined.
Concept introduction:
The Gibb’s equation of
With the help of this equation one can predict the change in
(b)
Interpretation:
The free energy change for the freezing of liquid water to the ice at 0°C needs to be determined.
Concept introduction:
The Gibb’s equation of thermodynamic purposed a relation between
With the help of this equation one can predict the change in
(c)
Interpretation:
The free energy change for the erosion of a mountain from the glacier needs to be determined.
Concept introduction:
The Gibb’s equation of thermodynamic purposed a relation between
With the help of this equation one can predict the change in
Want to see the full answer?
Check out a sample textbook solutionChapter 9 Solutions
CHEMISTRY-W/MASTERING CHEMISTRY ACCESS
- The decomposition of ozone, O3, to oxygen, O2, is an exothermic reaction. What is the sign of q? If you were to touch a flask in which ozone is decomposing to oxygen, would you expect the flask to feel warm or cool?arrow_forwardAt 298 K, the standard enthalpies of formation for C2H2(g) and C6H6(l) are 227 kJ/mol and 49 kJ/mol, respectively. a. Calculate H for C6H6(l)3C2H2(g) b. Both acetylene (C2H2) and benzene (C6H6) can be used as fuels. Which compound would liberate more energy per gram when combusted in air?arrow_forward9.42 Why is enthalpy generally more useful than internal energy in the thermodynamics of real world systems?arrow_forward
- The process of dissolving ammonium nitrate, NH4NO3, in water is an endothermic process. What is the sign of q? If you were to add some ammonium nitrate to water in a flask, would you expect the flask to feel warm or cool?arrow_forwardCoal is used as a fuel in some electric-generating plants. Coal is a complex material, but for simplicity we may consider it to be a form of carbon. The energy that can be derived from a fuel is sometimes compared with the enthalpy of the combustion reaction: C(s)+O2(g)CO2(g) Calculate the standard enthalpy change for this reaction at 25C. Actually, only a fraction of the heat from this reaction is available to produce electric energy. In electric generating plants, this reaction is used to generate heat for a steam engine, which turns the generator. Basically the steam engine is a type of heat engine in which steam enters the engine at high temperature (Th), work is done, and the steam then exits at a lower temperature (Tl). The maximum fraction, f, of heat available to produce useful energy depends on the difference between these temperatures (expressed in kelvins), f = (Th Tl)/Th. What is the maximum heat energy available for useful work from the combustion of 1.00 mol of C(s) to CO2(g)? (Assume the value of H calculated at 25C for the heat obtained in the generator.) It is possible to consider more efficient ways to obtain useful energy from a fuel. For example, methane can be burned in a fuel cell to generate electricity directly. The maximum useful energy obtained in these cases is the maximum work, which equals the free-energy change. Calculate the standard free-energy change for the combustion of 1.00 mol of C(s) to CO2(g). Compare this value with the maximum obtained with the heat engine described here.arrow_forward9.41 Under what conditions does the enthalpy change equal the heat of a process?arrow_forward
- Use Appendix L to find the standard enthalpies of formation of oxygen atoms, oxygen molecules (O2), and ozone (O3). What is the standard state of oxygen? Is the formation of oxygen atoms from O2 exothermic? What is the enthalpy change for the formation of 1 mol of O3 from O2?arrow_forwardThe combustion of methane can be represented as follows: a. Use the information given above to determine the value of H for the combustion of methane to form CO2(g) and 2H2O(l). b. What is Hf for an element in its standard state? Why is this? Use the figure above to support your answer. c. How does H for the reaction CO2(g) + 2H2O (1) CH4(g) + O2(g) compare to that of the combustion of methane? Why is this?arrow_forwardConsider the Haber process: N2(g)+3H2(g)2NH3(g);H=91.8kJ The density of ammonia at 25C and 1.00 atm is 0.696 g/L. The density of nitrogen, N2, is 1.145 g/L, and the molar heat capacity is 29.12 J/(mol C). (a) How much heat is evolved in the production of 1.00 L of ammonia at 25C and 1.00 atm? (b) What percentage of this heat is required to heat the nitrogen required for this reaction (0.500 L) from 25C to 400C, the temperature at which the Haber process is run?arrow_forward
- The enthalpy change for the following reaction is 393.5 kJ. C(s,graphite)+O2(g)CO2(g) (a) Is energy released from or absorbed by the system in this reaction? (b) What quantities of reactants and products are assumed? (c) Predict the enthalpy change observed when 3.00 g carbon burns in an excess of oxygen.arrow_forwardFrom the data given in Appendix I, determine the standard enthalpy change and the standard free energy change for each of the following reactions: (a) BF3(g)+3H2O(l)B(OH)3(s)+3HF(g) (b) BCl3(g)+3H2O(l)B(OH)3+3HCl(g) (c) B2H6(g)+6H2O(l)2B(OH)3(s)+6H2(g)arrow_forwardWrite the balanced chemical equation for the combustion of benzene, C6H6(l), to give carbon dioxide and water vapor. Would you expect S to be positive or negative in this process?arrow_forward
- Chemistry by OpenStax (2015-05-04)ChemistryISBN:9781938168390Author:Klaus Theopold, Richard H Langley, Paul Flowers, William R. Robinson, Mark BlaserPublisher:OpenStaxChemistry for Engineering StudentsChemistryISBN:9781337398909Author:Lawrence S. Brown, Tom HolmePublisher:Cengage LearningChemistry: Matter and ChangeChemistryISBN:9780078746376Author:Dinah Zike, Laurel Dingrando, Nicholas Hainen, Cheryl WistromPublisher:Glencoe/McGraw-Hill School Pub Co
- Chemistry: Principles and PracticeChemistryISBN:9780534420123Author:Daniel L. Reger, Scott R. Goode, David W. Ball, Edward MercerPublisher:Cengage LearningGeneral Chemistry - Standalone book (MindTap Cour...ChemistryISBN:9781305580343Author:Steven D. Gammon, Ebbing, Darrell Ebbing, Steven D., Darrell; Gammon, Darrell Ebbing; Steven D. Gammon, Darrell D.; Gammon, Ebbing; Steven D. Gammon; DarrellPublisher:Cengage LearningChemistry & Chemical ReactivityChemistryISBN:9781337399074Author:John C. Kotz, Paul M. Treichel, John Townsend, David TreichelPublisher:Cengage Learning