Question 7 (5 marks) Solid gold adopts the fcc structure. (i) Determine the number of Au atoms per fundamental unit cell (nuc); (ii) determine the volume of the fundamental unit cell (Vuc in nm3); (iii) determine the radius of a single Au atom (in nm); (iv) the volume (space) within the fundamental unit cell occupied by these Au atoms (Vs in nm3); (v) calculate its packing fraction; (vi) calculate the mass of a fundamental unit cell (muc in g); and (vii) the density (in g cm3 and in kg m3) of solid gold at T = 298.15 K. The molar mass of Au is MAu = 196.967 g mol1. The lattice parameter of Au equals a = 0.408 nm (at T = 298.15 K). Solution