HW 2 Inorganic Materials Chemistry Name: Points: C7780 Date: Max. 100 points Fall 2008 A 1. Assume that CaO reacts with CeO2 and forms CaCeO3. What could be the structure type of this compound? ______________ Write balanced chemical equations for the reactions taking place at the interfaces (assume counter diffusion of both cations) and calculate the Kirkendall ratio for this process. I II CaO CeO2CaCeO3 2. X-ray radiation of a Cu anode ( = 1.54 ) was diffracted under an angle of 14.22 at silicon crystal. Calculate the interplanar distance d in Si for the first order diffraction (n = 1). 3. Derive Miller indices for planes that intersects the cell axes at a/2, 2b/3, 2c. 4. Specific surface area of -Fe2O3 was measured by nitrogen adsorption at 77 K and its value is 120 m2 g-1 . Density of this oxide is 5.277 g cm-3 . Calculate the particle size assuming a spherical particle shape. 5. Maghemite -Fe2O3 crystallizes in a defect inverse spinel structure (as Fe3O4), but some positions of Fe3+ in octahedral holes must be vacant, in order to maintain stoichiometry. What part of these holes must be empty in comparison with Fe3O4. = empty hole, (X) = tetrahedral position, [Y] = octahedral position (Fe)___ [Fe___, ____] O4