2. (a) Prove that the ideal c/a ratio for the hexagonal close-packed structure is √√8/3=1.633. (b) Sodium transforms from bcc to hcp at about 23K (the "martensitic" transformation). Assuming that the density remains fixed through this transition, find the lattice constant a of the hexagonal phase, given that a=4.23Å in the cubic phase and that c/a ratio is ideal in the hcp phase.

2. (a) Prove that the ideal c/a ratio for the hexagonal close-packed structure is √√8/3=1.633. (b) Sodium transforms from bcc to hcp at about 23K (the "martensitic" transformation). Assuming that the density remains fixed through this transition, find the lattice constant a of the hexagonal phase, given that a=4.23Å in the cubic phase and that c/a ratio is ideal in the hcp phase.

Chemistry

10th Edition

ISBN:9781305957404

Author:Steven S. Zumdahl, Susan A. Zumdahl, Donald J. DeCoste

Publisher:Steven S. Zumdahl, Susan A. Zumdahl, Donald J. DeCoste

Chapter1: Chemical Foundations

Section: Chapter Questions

Problem 1RQ: Define and explain the differences between the following terms. a. law and theory b. theory and...

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