(a) What is the difference between atomic structure and crystalstructure
(b) Sketch the BCC and the FCC unit cells and show that theatomic packing factor for a BCC unit cell is 0.68.
(c) Molybdenum has a BCC unit cell, has an atomic radius of0.1363 nm, and an atomic weight of 95.94 g mol. Compute itstheoretical density and compare your answer with its experimentallymeasured density of 10.22 g cm³. The Avogadro’s number is6.023x1023 atoms mol- and 1 nm is 109 m.
(d) What is a polymorphic (allotropic) phase change? Giveexample.
