Q. Calculate the approximate number of unit cells present in 1 g gold.Given that gold crystallises in the fcc lattice.( Atomic mass of gold=197 u)
Ans:- 1 mole of Gold =197 g =6.02 × 10^23 atoms
as fcc lattice contains 4 atoms
∴ No. of unit cells present = 6.02 × 10^23 atoms /(197×4)
=7.64 × 10^20