Chemistry & Chemical Reactivity
Chemistry & Chemical Reactivity
10th Edition
ISBN: 9781337399074
Author: John C. Kotz, Paul M. Treichel, John Townsend, David Treichel
Publisher: Cengage Learning
bartleby

Videos

Textbook Question
Chapter 18, Problem 58GQ

Calculate ΔS°(system), ΔS°(surroundings), and ΔS°(universe) for each of the following processes at 298 K, and comment on how these systems differ.

  1. (a) HNO3(g) → HNO3(aq)
  2. (b) NaOH(s) → NaOH(aq)

(a)

Expert Solution
Check Mark
Interpretation Introduction

Interpretation:

The entropy change for the system, surroundings and universe for the given reaction should be calculated and commented how this system differs.

Concept introduction:

The universe consists of two parts, systems and surroundings. The entropy change for the universe is the sum of entropy change for the system and for surroundings.

  ΔSo(universe)= ΔSo(system)+ΔSo(surroundings)

The ΔSo(universe) should be greater than zero for a spontaneous process.

The  ΔSo(system) can be calculated by the following expression,

  ΔSo(system)rS°nS°(products)-nS°(reactants)

The ΔSo(surroundings) can be calculated by the following expression,

  ΔSo(surroundings)=rHoT

Here, ΔrHo is the enthalpy change for the reaction.

Answer to Problem 58GQ

The  ΔSo(system) for the formation of HNO3(aq) is 119.98 J/Kmol-rxn.

The ΔSo(surroundings) for the formation of HNO3(aq) is +242.49 J/Kmol-rxn.

The ΔSo(universe) for the formation of HNO3(aq) is +122.51 J/Kmol-rxn.

Explanation of Solution

The entropy change for the system, surroundings and universe for the given reaction is calculated below.

Given:

The Appendix L referred for the values of standard entropies and enthalpies.

The standard entropy of HNO3(g) is 266.38 J/Kmol.

The standard entropy of HNO3(aq) is 146.4 J/Kmol.

The standard enthalpy of HNO3(g) is 135.06 kJ/mol.

The standard enthalpy of HNO3(aq) is 207.36 kJ/mol.

The balanced chemical equation is:

  HNO3(g)HNO3(aq)

The  ΔSo(system) can be calculated by the following expression,

ΔSo(system)rS°nS°(products)-nS°(reactants)=[(1 mol HNO3(aq)/mol-rxn)S°[HNO3(aq)]-(1 mol HNO3(g)/mol-rxn)S°[HNO3(g)]]

Substituting the respective values

  ΔSo(system)=[(1 mol HNO3(aq)/mol-rxn)(146.4 J/K×mol)-(1 mol HNO3(g)/mol-rxn)(266.38 J/K×mol)]=-119.98 J/K×mol-rxn

The ΔrHo can be calculated by the following expression,

ΔrH°=fH°(products)fH°(reactants)=[(1 mol HNO3(aq)/mol-rxn)ΔfH°[HNO3(aq)]-(1 mol HNO3(g)/mol-rxn)ΔfH°[HNO3(g)]]

Substituting the respective values

ΔrH°=[(1 mol HNO3(aq)/mol-rxn)(-207.36 kJ/mol)-(1 mol HNO3(g)/mol-rxn)(-135.06 kJ/mol)]=-72.3 kJ/mol-rxn

The ΔSo(surroundings) can be calculated by the following expression,

  ΔSo(surroundings)rHoT= -[-72.3 kJ/mol-rxn298.15 K](1000JkJ)= +242.49 J/K×mol-rxn

Now,

  ΔSo(universe)= ΔSo(system)+ΔSo(surroundings)=(-119.98 J/K×mol-rxn)+(+242.49 J/K×mol-rxn)=+122.51 J/K×mol-rxn

The  ΔSo(system) for the formation of HNO3(aq) is 119.98 J/Kmol-rxn.

The ΔSo(surroundings) for the formation of HNO3(aq) is +242.49 J/Kmol-rxn.

The ΔSo(universe) for the formation of HNO3(aq) is +122.51 J/Kmol-rxn.

The given reaction is exothermic. There is more decrease in entropy in formation of HNO3(aq) from HNO3(g) due to decrease in number of moles of gases.

(b)

Expert Solution
Check Mark
Interpretation Introduction

Interpretation:

The entropy change for the system, surroundings and universe for the given reaction should be calculated and commented how this system differs.

Concept introduction:

The universe consists of two parts, systems and surroundings. The entropy change for the universe is the sum of entropy change for the system and for surroundings.

  ΔSo(universe)= ΔSo(system)+ΔSo(surroundings)

The ΔSo(universe) should be greater than zero for a spontaneous process.

The  ΔSo(system) can be calculated by the following expression,

  ΔSo(system)rS°nS°(products)-nS°(reactants)

The ΔSo(surroundings) can be calculated by the following expression,

  ΔSo(surroundings)=rHoT

Here, ΔrHo is the enthalpy change for the reaction.

Answer to Problem 58GQ

The  ΔSo(system) for the formation of NaOH(aq) is 16.36 J/Kmol-rxn.

The ΔSo(surroundings) for the formation of NaOH(aq) is +144.96 J/Kmol-rxn.

The ΔSo(universe) for the formation of NaOH(aq) is +128.6 J/Kmol-rxn.

Explanation of Solution

The entropy change for the system, surroundings and universe for the given reaction is calculated below.

Given:

The Appendix L referred for the values of standard entropies and enthalpies.

The standard entropy of NaOH(s) is 64.46 J/Kmol.

The standard entropy of NaOH(aq) is 48.1 J/Kmol.

The standard enthalpy of NaOH(s) is 425.93 kJ/mol.

The standard enthalpy of NaOH(aq) is 469.15 kJ/mol.

The balanced chemical equation is:

  NaOH(s)NaOH(aq)

The  ΔSo(system) can be calculated by the following expression,

  ΔS(system)=ΔrS°nS°(products)-nS°(reactants)=[(1 mol NaOH(aq)/mol-rxn)S°[NaOH(aq)](1 mol NaOH(s)/mol-rxn)S°[NaOH(s)]]

Substituting the respective values

ΔSo(system)=[(1 mol NaOH(aq)/mol-rxn)(48.1 J/K×mol)-(1 mol NaOH(s)/mol-rxn)(64.46 J/K×mol)]=-16.36 J/K×mol-rxn

The ΔrHo can be calculated by the following expression,

ΔrH°=fH°(products)fH°(reactants)=[(1 mol NaOH(aq)/mol-rxn)ΔfH°[NaOH(aq)](1 mol NaOH(s)/mol-rxn)ΔfH°[NaOH(s)]]

Substituting the respective values

  ΔrH°=[(1 mol NaOH(aq)/mol-rxn)(-469.15 kJ/mol)-(1 mol NaOH(s)/mol-rxn)(-425.93 kJ/mol)]= -43.22 kJ/mol-rxn

The ΔSo(surroundings) can be calculated by the following expression,

  ΔSo(surroundings)=rHoT=-[-43.22 kJ/mol-rxn298.15 K](1000JkJ)=+144.96 J/K×mol-rxn

Now,

ΔSo(universe)= ΔSo(system)+ΔSo(surroundings)(-16.36 J/K×mol-rxn)+(+144.96 J/K×mol-rxn)= +128.6 J/K×mol-rxn

The  ΔSo(system) for the formation of NaOH(aq) is 16.36 J/Kmol-rxn.

The ΔSo(surroundings) for the formation of NaOH(aq) is +144.96 J/Kmol-rxn.

The ΔSo(universe) for the formation of NaOH(aq) is +128.6 J/Kmol-rxn.

The given reactions is exothermic. The entropy change for the formation of NaOH(aq) from NaOH(s) should be positive. However, the value is negative due to hydrogen bonding.

Want to see more full solutions like this?

Subscribe now to access step-by-step solutions to millions of textbook problems written by subject matter experts!

Chapter 18 Solutions

Chemistry & Chemical Reactivity

Ch. 18.7 - Prob. 1.2ACPCh. 18.7 - The decomposition of diamond to graphite...Ch. 18.7 - It has been demonstrated that buckminsterfullerene...Ch. 18 - Solid NH4NO3 is placed in a beaker containing...Ch. 18 - Acetic acid, a weak acid, was added to a beaker...Ch. 18 - Identify the following processes as either...Ch. 18 - Identify the following processes as either...Ch. 18 - Prob. 5PSCh. 18 - Predict whether each of the following processes...Ch. 18 - Indicate which of the following processes are...Ch. 18 - Prob. 8PSCh. 18 - Prob. 9PSCh. 18 - Prob. 10PSCh. 18 - Prob. 11PSCh. 18 - Calculate the entropy change that occurs when 1.00...Ch. 18 - Prob. 13PSCh. 18 - Calculate the change in entropy of a system with...Ch. 18 - The third law of thermodynamics says that a...Ch. 18 - Identify trends in S values: (a) For the halogens:...Ch. 18 - Which substance has the higher entropy? (a) dry...Ch. 18 - Which substance has the higher entropy? (a) a...Ch. 18 - Use S values to calculate the standard entropy...Ch. 18 - Use S values to calculate the standard entropy...Ch. 18 - Calculate the standard entropy change for the...Ch. 18 - Calculate the standard entropy change for the...Ch. 18 - Calculate the standard entropy change for the...Ch. 18 - Calculate the standard entropy change for the...Ch. 18 - Is the reaction Si(s) + 2 Cl2(g) SiCl4(g)...Ch. 18 - Is the reaction Si(s) + 2 H2(g) SiH4(g)...Ch. 18 - Calculate S(universe) for the decomposition of 1...Ch. 18 - Calculate S(universe) for the formation of 1 mol...Ch. 18 - Classify each of the reactions according to one of...Ch. 18 - Classify each of the reactions according to one of...Ch. 18 - Using values of fH and S, calculate rG for each of...Ch. 18 - Using values of fH and S, calculate rG for each of...Ch. 18 - Using values of fH and S, calculate the standard...Ch. 18 - Using values of fH and S, calculate the standard...Ch. 18 - Using values of fG, calculate rG for each of the...Ch. 18 - Using values of fG, calculate rG for each of the...Ch. 18 - For the reaction BaCO3(s) BaO(s) + CO2(g), rG =...Ch. 18 - For the reaction TiCl2(s) + Cl2(g) TiCl4(), rG =...Ch. 18 - Determine whether the reactions listed below are...Ch. 18 - Determine whether the reactions listed below are...Ch. 18 - Heating some metal carbonates, among them...Ch. 18 - Calculate rH and rS for the reaction of tin(IV)...Ch. 18 - The ionization constant, Ka, for acetic acid is...Ch. 18 - Prob. 44PSCh. 18 - The standard free energy change, rG, for the...Ch. 18 - Prob. 46PSCh. 18 - Calculate rG at 25 C for the formation of 1.00 mol...Ch. 18 - Prob. 48PSCh. 18 - Prob. 49PSCh. 18 - Prob. 50PSCh. 18 - Compare the compounds in each set below and decide...Ch. 18 - Using standard entropy values, calculate rS for...Ch. 18 - About 5 billion kilograms of benzene, C6H6, are...Ch. 18 - Hydrogenation, the addition of hydrogen to an...Ch. 18 - Is the combustion of ethane, C2H6, product-favored...Ch. 18 - Prob. 56GQCh. 18 - When vapors from hydrochloric acid and aqueous...Ch. 18 - Calculate S(system), S(surroundings), and...Ch. 18 - Methanol is now widely used as a fuel in race...Ch. 18 - The enthalpy of vaporization of liquid diethyl...Ch. 18 - Calculate the entropy change, rS, for the...Ch. 18 - Using thermodynamic data, estimate the normal...Ch. 18 - Prob. 63GQCh. 18 - When calcium carbonate is heated strongly, CO2 gas...Ch. 18 - Sodium reacts violently with water according to...Ch. 18 - Yeast can produce ethanol by the fermentation of...Ch. 18 - Elemental boron, in the form of thin fibers, can...Ch. 18 - Prob. 68GQCh. 18 - Prob. 69GQCh. 18 - Estimate the boiling point of water in Denver,...Ch. 18 - The equilibrium constant for the butane ...Ch. 18 - A crucial reaction for the production of synthetic...Ch. 18 - Calculate rG for the decomposition of sulfur...Ch. 18 - Prob. 74GQCh. 18 - A cave in Mexico was recently discovered to have...Ch. 18 - Wet limestone is used to scrub SO2 gas from the...Ch. 18 - Sulfur undergoes a phase transition between 80 and...Ch. 18 - Calculate the entropy change for dissolving HCl...Ch. 18 - Some metal oxides can be decomposed to the metal...Ch. 18 - Prob. 80ILCh. 18 - Prob. 81ILCh. 18 - Prob. 82ILCh. 18 - Titanium(IV) oxide is converted to titanium...Ch. 18 - Cisplatin [cis-diamminedichloroplatinum(II)] is a...Ch. 18 - Prob. 85ILCh. 18 - Explain why each of the following statements is...Ch. 18 - Decide whether each of the following statements is...Ch. 18 - Under what conditions is the entropy of a pure...Ch. 18 - Prob. 89SCQCh. 18 - Consider the formation of NO(g) from its elements....Ch. 18 - Prob. 91SCQCh. 18 - The normal melting point of benzene, C6H6, is 5.5...Ch. 18 - Prob. 93SCQCh. 18 - For each of the following processes, predict the...Ch. 18 - Heater Meals are food packages that contain their...Ch. 18 - Prob. 96SCQCh. 18 - Prob. 97SCQCh. 18 - Prob. 98SCQCh. 18 - Iodine, I2, dissolves readily in carbon...Ch. 18 - Prob. 100SCQCh. 18 - Prob. 101SCQCh. 18 - Prob. 102SCQCh. 18 - Prob. 103SCQCh. 18 - Prob. 104SCQCh. 18 - The Haber-Bosch process for the production of...Ch. 18 - Prob. 106SCQCh. 18 - Prob. 107SCQ
Knowledge Booster
Chemistry
Learn more about
Need a deep-dive on the concept behind this application? Look no further. Learn more about this topic, chemistry and related others by exploring similar questions and additional content below.
Similar questions
    • SEE MORE QUESTIONS
    Recommended textbooks for you
  • Chemistry for Engineering Students
    Chemistry
    ISBN:9781337398909
    Author:Lawrence S. Brown, Tom Holme
    Publisher:Cengage Learning
    Chemistry: Principles and Reactions
    Chemistry
    ISBN:9781305079373
    Author:William L. Masterton, Cecile N. Hurley
    Publisher:Cengage Learning
    Chemistry: Principles and Practice
    Chemistry
    ISBN:9780534420123
    Author:Daniel L. Reger, Scott R. Goode, David W. Ball, Edward Mercer
    Publisher:Cengage Learning
  • Chemistry
    Chemistry
    ISBN:9781133611097
    Author:Steven S. Zumdahl
    Publisher:Cengage Learning
    Chemistry
    Chemistry
    ISBN:9781305957404
    Author:Steven S. Zumdahl, Susan A. Zumdahl, Donald J. DeCoste
    Publisher:Cengage Learning
    Chemistry: An Atoms First Approach
    Chemistry
    ISBN:9781305079243
    Author:Steven S. Zumdahl, Susan A. Zumdahl
    Publisher:Cengage Learning
  • Chemistry for Engineering Students
    Chemistry
    ISBN:9781337398909
    Author:Lawrence S. Brown, Tom Holme
    Publisher:Cengage Learning
    Chemistry: Principles and Reactions
    Chemistry
    ISBN:9781305079373
    Author:William L. Masterton, Cecile N. Hurley
    Publisher:Cengage Learning
    Chemistry: Principles and Practice
    Chemistry
    ISBN:9780534420123
    Author:Daniel L. Reger, Scott R. Goode, David W. Ball, Edward Mercer
    Publisher:Cengage Learning
    Chemistry
    Chemistry
    ISBN:9781133611097
    Author:Steven S. Zumdahl
    Publisher:Cengage Learning
    Chemistry
    Chemistry
    ISBN:9781305957404
    Author:Steven S. Zumdahl, Susan A. Zumdahl, Donald J. DeCoste
    Publisher:Cengage Learning
    Chemistry: An Atoms First Approach
    Chemistry
    ISBN:9781305079243
    Author:Steven S. Zumdahl, Susan A. Zumdahl
    Publisher:Cengage Learning
    The Laws of Thermodynamics, Entropy, and Gibbs Free Energy; Author: Professor Dave Explains;https://www.youtube.com/watch?v=8N1BxHgsoOw;License: Standard YouTube License, CC-BY