ENGG 027 Fall 2013 Dr. Goldberg Homework #1, due Mon, Sept. 16th Electron structure 1) Write the electron configuration for Si1+ and Zn1-. Explain why these two ions should behave similarly. Bonding force and energy 2) Using the ionic radii given in the table on the inside cover of your text calculate the coulombic force of attraction between Na+ and Cl-when these ions are bonded (i.e. at the equilibrium bond distance). Note the units of the values in the table. You may assume that the ions are as close as possible without overlapping when they are at the equilibrium bond distance. 3) What is the repulsive force in this case? Explain your answer. 4) What would happen to the energy of the bond if the bond were lengthened or shortened? Explain your answer. 5) The bond force curves for two materials, A and B, are shown below as a function of bond length. If identically shaped beams were fabricated from each material, which would show a greater deflection under equal applied loads? Explain your choice. Bond type 6) What type of bonding (metallic, ionic, dipole, covalent) would you expect for each of the following materials (give primary and secondary, where appropriate). Give justification for your answers: a) calcium fluoride (CaF2) b) cadmium telluride (CdTe) c) rubber (composed of long chains of carbon (C) with hydrogen (H) attached to carbon chain) d) solid tungsten (chemical formula W) Interatomic bond force Interatomic bond distance