Which of the following statements concerning crystal structure is NOT true?

W) HCP lattices are more space-filling than FCC lattices

X) Cesium [SEEZ-ee-um] chloride lattices form when anions [AN-eye-ons] and cations [CAT-eye-onz] are of roughly equal size

Y) Rock-salt lattices have (6,-coordination

Z) The crystal structure of a metal is dependent on pressure and temperature
W) HCP LATTICES ARE MORE SPACE-FILLING THAN FCC LATTICES