Tungsten is usually produced by the reduction of WO3 with hydrogen:
Consider the following data:
WO3(s) | H2O(g) | ||
|
−839.9 | −241.8 | |
|
−763–1 | −228.6 |
- a It K > 1 or < 1 at 25°C? Explain your answer.
- b What is the value of ΔS° at 25°C?
- c What is the temperature at which ΔG° equals zero for this reaction at 1 atm pressure?
- d What is the driving force of this reaction?
(a)
Interpretation:
For the given reaction, the value of
Concept introduction:
Standard free energy change:
Standard free energy change is measured by subtracting the product of temperature and standard entropy change from the standard enthalpy change of a system.
Spontaneous process:
The chemical or physical change can takes place by itself without the help of surroundings are called as spontaneous process.
Answer to Problem 18.92QP
For the given reaction the sign of free energy change
Explanation of Solution
To calculate: The value of
Given reaction and information,
Calculate the value of
The sign of free energy change
(b)
Interpretation:
For the given reaction, the value of
Concept introduction:
Standard free energy change:
Standard free energy change is measured by subtracting the product of temperature and standard entropy change from the standard enthalpy change of a system.
Spontaneous process:
The chemical or physical change can takes place by itself without the help of surroundings are called as spontaneous process.
Answer to Problem 18.92QP
The value of entropy change
Explanation of Solution
To calculate: The value of
Calculate the value of
Calculate the value of
The value of entropy change
(c)
Interpretation:
For the given reaction, the value of
Concept introduction:
Standard free energy change:
Standard free energy change is measured by subtracting the product of temperature and standard entropy change from the standard enthalpy change of a system.
Spontaneous process:
The chemical or physical change can takes place by itself without the help of surroundings are called as spontaneous process.
Answer to Problem 18.92QP
At temperature
Explanation of Solution
To calculate: At which temperature the free energy change equals to zero
Consider free energy change
The value of
(d)
Interpretation:
For the given reaction, the value of
Concept introduction:
Standard free energy change:
Standard free energy change is measured by subtracting the product of temperature and standard entropy change from the standard enthalpy change of a system.
Spontaneous process:
The chemical or physical change can takes place by itself without the help of surroundings are called as spontaneous process.
Answer to Problem 18.92QP
The entropy change is the driving force. The value of
Explanation of Solution
To identify: The driving force for the given reaction
The entropy change is the driving force.
The value of
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Chapter 18 Solutions
General Chemistry
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- Using data from Appendix 4, calculate G for the reaction 2H2S(g)+SO2(g)3Srhombic(s)+2H2O(g) for the following conditions at 25C: PH2S=1.0104atmPSO2=1.0102atmPH2O=3.0102atmarrow_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_forwardWhat information can be determined from G for a reaction? Does one get the same information from G, the standard free energy change? G allows determination of the equilibrium constant K for a reaction. How? How can one estimate the value of K at temperatures other than 25C for a reaction? How can one estimate the temperature where K = 1 for a reaction? Do all reactions have a specific temperature where K = 1?arrow_forward
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