Concept explainers
The number of atoms in a critically sized nucleus for the homogeneous nucleation of pure platinum.
Answer to Problem 33AAP
The number of atoms in a critically sized nucleus for the homogeneous nucleation of pure platinum is
Explanation of Solution
Express the volume of critical size nucleus.
Here, critical radius is
Since platinum has a FCC structure, each unit cell has 4 atoms.
Express the volume of platinum.
Here, side of a FCC unit cell is
Express the volume per atom.
Here, number of atoms per FCC unit cell is
Express the number of atoms in a critically sized nucleus for the homogeneous nucleation of pure platinum.
Conclusion:
For platinum, write the critical radius as:
Write the side of a FCC platinum unit cell.
Substitute
Substitute
Substitute
Substitute
Hence, the number of atoms in a critically sized nucleus for the homogeneous nucleation of pure platinum is
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Chapter 4 Solutions
Foundations of Materials Science and Engineering
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