Unformatted text preview: character is more covalent than ionic. F Polymers typically contain both covalent and secondary bonding. T The non-directional nature of the metallic bond results in crystals with low coordination numbers. F (1 point each) Label the following as characteristics of strong bonds ( S ) or weak bonds ( W ). low melting point W short bond length S large thermal expansion coefficient W large elastic modulus S (3 points) What are the coordination numbers (number of nearest neighbors) for FCC, HCP, and body centered cubic (BCC) crystal structures? FCC CN = 12 HCP CN = 12 BCC CN = 8 (2 points) How many atoms are contained inside of the unit cell for FCC and BCC crystals? FCC 4 atoms/UC BCC 2 atoms/UC (3 points) Calculate the atomic radii for gold (FCC with a = 0.4078 nm). Use the correct number of significant figures for the correct answer. a) 0.1766 nm b) 0.1442 nm c) 0.177 nm d) 0.144 nm...
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This note was uploaded on 02/24/2009 for the course MSE 150 taught by Professor Wittig during the Spring '07 term at Vanderbilt.
- Spring '07