1.Ceramic MgO can be obtained by chemical reaction of Mg metal with Oxygen. The ionic radius for Mg2+ and O2- are 0.072 nm and 0.14 nm, respectively. Therefore, you can predict the coordination number for Mg is:

a. 3

b. 4

c. 6

d. 8 12.

2/ For Gold (Au), it is known that the atomic radius is 0.144 nm and it has a FCC crystal structure. Please calculate the theoretical density of Au:

a. 19.32 g/cm3

b. 19.35 g/cm3

c. 9.66 g/cm3

d. 9.68 g/cm3