Copper has an FCC crystal structure and an atomic radius of 1.278 × 10−10 m. Assuming the atoms
to be hard spheres that touch each other along the face diagonals of the FCC unit cell as shown for
one of the faces in Figure Q2, Determine:
(a) The lattice constant of the copper unit cell. (4marks)
(b) The atomic packing factor (APF) for the copper unit cell. (5 marks)
(c) The theoretical value for the density of copper in /3
. (5 marks)
(The atomic mass of copper is 63.54 g/mole and Avogadro’s number = 6.023 x 1023 atoms/mole)



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