Determine whether the reactions listed below are entropy-favored or disfavored under standard conditions. Predict how an increase in temperature will affect the value of ΔrG°.
- (a) I2(g) → 2 I(g)
- (b) 2 SO2(g) + O2(g) → 2 SO3(g)
- (c) SiCl4(g) + 2 H2O(ℓ) → SiO2(s) + 4 HCl(g)
- (d) P4(s, white) + 6 H2(g) → 4 PH3(g)
(a)
Interpretation:
It should be determined that whether the given reaction is entropy favorable and should be identified that how increase in temperature will affect the value of
Concept introduction:
The Gibbs free energy or the free energy change is a thermodynamic quantity represented by
Here,
Entropy for any reaction is expressed as,
A reaction is said to be entropy-favored if the value of entropy change for reaction is positive.
Answer to Problem 40PS
The formation of
Explanation of Solution
The value of
Given:
The Appendix L referred for the values of standard entropies and enthalpies.
Substituting the respective values
Also,
Substituting the respective values
Now,
Substitute the value of
The formation of
The reaction will become product-favored at higher temperature.
(b)
Interpretation:
It should be determined that whether the given reaction is entropy favorable and should be identified that how increase in temperature will affect the value of
Concept introduction:
The Gibbs free energy or the free energy change is a thermodynamic quantity represented by
Here,
Entropy for any reaction is expressed as,
A reaction is said to be entropy-favoured if the value of entropy change for reaction is positive.
Answer to Problem 40PS
The formation of
Explanation of Solution
The value of
Given:
The Appendix L referred for the values of standard entropies and enthalpies.
The standard enthalpy change is expressed as,
Substituting the respective values
Also,
Substituting the respective values
Now,
Substitute the value of
The formation of
(c)
Interpretation:
It should be determined that whether the given reaction is entropy favorable and should be identified that how increase in temperature will affect the value of
Concept introduction:
The Gibbs free energy or the free energy change is a thermodynamic quantity represented by
Here,
Entropy for any reaction is expressed as,
A reaction is said to be entropy-favoured if the value of entropy change for reaction is positive.
Answer to Problem 40PS
The reaction of
Explanation of Solution
The Appendix L referred for values for the values of standard entropies and enthalpies.
The standard enthalpy change is expressed as,
Substituting the respective values
Also,
Substituting the respective values
Now,
Substitute the value of
The reaction of
(d)
Interpretation:
It should be determined that whether the given reaction is entropy favorable and should be identified that how increase in temperature will affect the value of
Concept introduction:
The Gibbs free energy or the free energy change is a thermodynamic quantity represented by
Here,
Entropy for any reaction is expressed as,
A reaction is said to be entropy-favoured if the value of entropy change for reaction is positive.
Answer to Problem 40PS
The reaction of
Explanation of Solution
The value of
Given:
The Appendix L referred for values of standard entropies and enthalpies.
The standard enthalpy change is expressed as,
Substituting the respective values
Also,
Substituting the respective values
Now,
Substitute the value of
The reaction of
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Chapter 18 Solutions
Chemistry & Chemical Reactivity
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