What kind of crystal structure would you expect for CaF2ioni

What kind of crystal structure would you expect for CaF-2(ionic radius of Ca^2+ and F^- is 0.100 and 0.133. respectively)? six anions are surrounding a cation only half of the cation sites are occupied exactly the same structure as CsCI exactly the same structure as NaCI Which of the following glasses has the highest temperature required to soften? soda lime glass borosilicate glass 96% silica glass fused silica glass Which one of the following statements is correct for comparison between homogeneous nucleation and heterogeneous nucleation? Homogeneous activation energy barrier is smaller Heterogeneous activation energy barrier is smaller Critical radius for homogeneous nucleation is smaller Critical radius for heterogeneous nucleation is smaller What is K_k? fracture toughness that depends on specimen size critical value of stress intensity factor toughness under plane stress condition ductility parameter Which material does NOT have the layered structure?

Solution

5.13 K_IC is a critical value of stress intensity factor option b

5.10 option b only half the cation sites are occupied

5.11 option a soda lime glass has highest temperature to soften

5.12 option b heterogenous activation energy have a much smaller barrier

5.14 option c zirconia is not a layered structure

5.15 option c carbon nano tubes is formed bt wrapping the graphite sheet