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 33PS
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 33PS
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 33PS
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
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- On 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_forwardThe combustion of acetylene, C2H2, is a spontaneous reaction given by the equation 2C2H2(g)+5O2(g)4CO2(g)+2H2O(l) As expected for a combustion, the reaction is exothermic. What is the sign of H? What do you expect for the sign of S? Explain the spontaneity of the reaction in terms of the enthalpy and entropy changes.arrow_forward
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