Compare the Packing Efficiency of Face-Centered Cubic Gold and Face-Centered

Multiple Choice

Compare the packing efficiency of face-centered cubic gold and face-centered cubic sodium chloride considering all the atoms.

A) The efficiency of packing in the gold unit cell is higher.
B) The efficiency of packing in the sodium chloride unit cell is higher.
C) The efficiencies of packing in the two lattices are the same.
D) Packing efficiencies cannot be defined for one or both of these.
E) There is no way to compare without further information.