Zinc sulfide, ZnS, exists in two main crystal forms. The more stable form, zinc blende, is face---centered cubic with tetrahedral coordination geometry and has density 4.09 g/cm3.
a.) Use 184 pm for the ionic radius of S2--- to calculate the ionic radius of Zn2+.
b.) What would be the density of a hypothetical form of ZnS that is face---centered cubic with octahedral, instead of tetrahedral, coordination geometry?
c.) If ZnS had primitive cubic unit cell instead, then what would be its density?