Concept explainers
The activation enthalpy and pre-exponential constant for the diffusion of oxygen
Answer to Problem 4.20P
The activation enthalpy is
Explanation of Solution
Formula used:
The diffusion coefficient of point
Here,
The diffusion coefficient of point
Here,
The ratio of diffusion coefficient of points
Calculation:
The activation enthalpy is calculated as,
Substitute
Solve further,
The diffusion coefficient is calculated as,
Substitute
Conclusion:
Therefore, the activation enthalpy is
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Chapter 4 Solutions
Materials Science And Engineering Properties
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- Materials Science And Engineering PropertiesCivil EngineeringISBN:9781111988609Author:Charles GilmorePublisher:Cengage Learning