Would you expect BeO to have the sodium chloride, zinc blende, or fluorite structure? Based on your answer, determine: i) the lattice parameter, ii) the density, and iii) the packing factor. (b) Sketch the ion arrangement on the (110) plane of ZnS (with the zinc blende structure) and compare this arrangement to that on the (110) plane of CaF2 (with the fluorite structure). Compare the planar packing fraction on the (110) planes for these two materials. (c)