Using values of ΔfH° and S°, calculate the standard molar free energy of formation, ΔfG°, for each of the following compounds:
- (a) CS2(g)
- (b) NaOH(s)
- (c) ICl(g)
Compare your calculated values of ΔfG° with those listed in Appendix L Which of these formation reactions are predicted to be product-favored at equilibrium at 25 °C?
(a)
Interpretation:
The the standard molar free energy for formation of
Concept Introduction:
The Gibbs free energy or the free energy change is a thermodynamic quantity represented by
Here,
Answer to Problem 17PS
The standard molar free energy of formation for
The value of
Explanation of Solution
The standard molar free energy of formation for
Given:
The Appendix L referred for the values of standard entropies and enthalpies.
Substituting the respective values,
Substituting the respective values,
Now,
Substituting the value of
The value listed in Appendix L is
The value of
(b)
Interpretation:
The the standard molar free energy for formation of
Concept Introduction:
The Gibbs free energy or the free energy change is a thermodynamic quantity represented by
Here,
Answer to Problem 17PS
The standard molar free energy of formation for
The value of
Explanation of Solution
The standard molar free energy of formation for
Given:
The Appendix L referred for the values of standard entropies and enthalpies.
Substituting the values,
Substituting the values,
Now,
Substitute the value of
The value listed in Appendix L is
The value of
(c)
Interpretation:
The the standard molar free energy for formation of
Concept Introduction:
The Gibbs free energy or the free energy change is a thermodynamic quantity represented by
Here,
Answer to Problem 17PS
The standard molar free energy of formation for
The value of
Explanation of Solution
The standard molar free energy of formation for
Given:
The Appendix L referred for the values of standard entropies and enthalpies.
Substituting the respective values,
Substituting the respective values,
Now,
Substituting the value of
The value listed in Appendix L is
The value of
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Chapter 18 Solutions
Chemistry & Chemical Reactivity
- Actually, the carbon in CO2(g) is thermodynamically unstable with respect to the carbon in calcium carbonate(limestone). Verify this by determining the standardGibbs free energy change for the reaction of lime,CaO(s), with CO2(g) to make CaCO3(s).arrow_forwardUsing values of fH and S, calculate rG for each of the following reactions at 25 C. (a) 2 Na(s) + 2 H2O() 2 NaOH(aq) + H2(g) (b) 6 C(graphite) + 3 H2(g) C6H6() Which of these reactions is (are) predicted to be product-favored at equilibrium? Are the reactions enthalpy- or entropy-driven?arrow_forwardThere are millions of organic compounds known, and new ones are being discovered or made at a rate of morethan 100,000 compounds per year. Organic compoundsburn readily in air at high temperatures to form carbondioxide and water. Several classes of organic compoundsare listed, with a simple example of each. Write a balanced chemical equation for the combustion in O2ofeach of these compounds, and then use the data inAppendix J to show that each reaction is product-favoredat room temperature. From these results, it is reasonable to hypothesize thatallorganic compounds are thermodynamically unstable inan oxygen atmosphere (that is, their room-temperaturereaction with O2(g) to form CO2(g) and H2O() isproduct-favored). If this hypothesis is true, how canorganic compounds exist on Earth?arrow_forward
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- For each of the following processes, identify the systemand the surroundings. Identify those processes that arespontaneous. For each spontaneous process, identify theconstraint that has been removed to enable the process to occur: Ammonium nitrate dissolves in water. Hydrogen and oxygen explode in a closed bomb. A rubber band is rapidly extended by a hangingweight. The gas in a chamber is slowly compressed by aweighted piston. A glass shatters on the floor.arrow_forwardUsing values of fH and S, calculate the standard molar free energy of formation, fG, for each of the following: (a) Ca(OH)2(s) (b) Cl(g) (c) Na2CO3(s) Compare your calculated values of fG with those listed in Appendix L. Which of these formation reactions are predicted to be product-favored at equilibrium at 25 C?arrow_forwardOn the basis of your experience, predict which reactions are spontaneous: (a) PbO2(s)Pb(s)+O2(g)(b) N2(l)N2(g) at 25C (c) C6H12O6(s)C6H12O6(l) at 25C (d) Ca2+(aq)+CO32(aq)CaCO3(s)arrow_forward
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