Interpretation:
The entropy changes
Concept Introduction:
In
The equation given below helps us to calculate the change in free energy in a system.
At a temperature of normal boiling point, the gaseous state of the system will be in equilibrium with the liquid state. The free energy change in the system will be zero. Taking the free energy value as zero, molar entropy of sublimation can be calculated using the following equation.
Where,
Want to see the full answer?
Check out a sample textbook solutionChapter 17 Solutions
Connect for Chemistry
- 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_forwardA green plant synthesizes glucose by photosynthesis, as shown in the reaction: 6CO2(g) + 6H2O(l) C6H12O6(s) + 6O2(g) Animals use glucose as a source of energy: C6H12O6(s) + 6O2(g) 6CO2(g) + 6HO2(l) If we were to assume that both of these processes occur to the same extent in a cyclic process, what thermodynamic property must have a nonzero value?arrow_forwardThe 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).arrow_forward
- Write 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_forwardWrite the balanced chemical equation for the combustion of methane, CH4(g), to give carbon dioxide and water vapor. Explain why it is difficult to predict whether S is positive or negative for this chemical reaction.arrow_forwardFor each of the following processes, predict the algebraic sign of rH, rS, and rG. No calculations are necessary; use your common sense. (a) The decomposition of liquid water to give gaseous oxygen and hydrogen, a process that requires a considerable amount of energy. (b) Dynamite is a mixture of nitroglycerin, C3H5N3O9, and diatomaceous earth. The explosive decomposition of nitroglycerin gives gaseous products such as water, CO2, and others; much heat is evolved. (c) The combustion of gasoline in the engine of your car, as exemplified by the combustion of octane. 2 C8H18(g) + 25 O2(g) 16 CO2(g) + 18 H2O(g)arrow_forward
- Using data from Appendix 4, calculate H, S and G for the following reactions that produce acetic acid: Which reaction would you choose as a commercial method for producing acetic acid (CH3CO2H) at standard conditions? What temperature conditions would you choose for the reaction? Assume H and S do not depend on temperature.arrow_forwardThe 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_forwardAre any of the following exothermic processes not spontaneous under any circumstances? (a) Snow forms from Liquid water. (b) Liquid water condenses from water vapor. (c) Fossil fuels burn to form carbon dioxide and water. (d) Monomers react to form a polymer.arrow_forward
- An industrial process for manufacturing sulfuric acid, H2SO4, uses hydrogen sulfide, H2S, from the purification of natural gas. In the first step of this process, the hydrogen sulfide is burned to obtain sulfur dioxide, SO2. 2H2S(g)+3O2(g)2H2O(l)+2SO2(g);H=1124kJ The density of sulfur dioxide at 25C and 1.00 atm is 2.62 g/L, and the molar heat capacity is 30.2 J/(mol C). (a) How much heat would be evolved in producing 1.00 L of SO2 at 25C and 1.00 atm? (b) Suppose heat from this reaction is used to heat 1.00 L of the SO2 from 25C to 500C for its use in the next step of the process. What percentage of the heat evolved is required for this?arrow_forwardThe normal melting point of benzene, C6H6, is 5.5 C. For the process of melting, what is the sign of each of the following? (a) rH (b) rS (c) rG at 5.5 C (d) rSG at 0.0 C (e) rG at 25.0 Carrow_forward9.47 If 14.8 kJ of heat is given off when 1.6 g of HCl condenses from vapor to liquid, what is Hcond for this substance?arrow_forward
- General 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: The Molecular ScienceChemistryISBN:9781285199047Author:John W. Moore, Conrad L. StanitskiPublisher:Cengage Learning
- Chemistry & Chemical ReactivityChemistryISBN:9781133949640Author:John C. Kotz, Paul M. Treichel, John Townsend, David TreichelPublisher:Cengage LearningChemistry & Chemical ReactivityChemistryISBN:9781337399074Author:John C. Kotz, Paul M. Treichel, John Townsend, David TreichelPublisher:Cengage LearningChemistry by OpenStax (2015-05-04)ChemistryISBN:9781938168390Author:Klaus Theopold, Richard H Langley, Paul Flowers, William R. Robinson, Mark BlaserPublisher:OpenStax