Some hypothetical alloy is composed of 25 wt% of metal A and 75 wt% of metal B. If the densities of metals A and B are 6.17 and 8.00 g/cm' respectively, whereas their respective atomic weights are 171.3 g/mol and 162 g/mol respectively, determine the crystalline structure of the alloy assuming a unit cell edge length of 0.332nm.

2. Answer ALL parts a) - c). Sodium ([Ne] 3s¹3pº) forms a simple cubic (sc) primitive crystal structure, in which Na atoms are arranged at the corners of a cube. a) How many atoms are contained in the unit cell, and how many valence bands can be expected?   b) Sketch the crystal orbitals at the special points ï'(0,0,0), X(1/2,1/2,0), and M(1/2,1/2,1/2), and hence draw the corresponding band structure along T-X-M-T. c) With the aid of a diagram, explain how the band structure would change if the cube was distorted into a rhombohedron by elongation along a body diagonal?

The angle of diffraction of (220) set of planes for an FCC element occurs at 69.22° when monochromatic x-radiation having a wavelength of 0.1542 nm is used. (a) Calculate the atomic radius of the element; (b) Calculate the angle of diffraction from the set of planes (310).

2. The ReO3 structure is cubic with a Re atom at each corner of the unit cell and one O atom on each unit cell edge midway between the Re atoms. Sketch the unit cell and determine a) the coordination number of each Re ion and b) the identity of the structure type that would be generated if a cation were to be inserted into the center of each ReO3 unit cell.