Question

Copper crystal has a face centred cubic structure. Atomic radius of copper atom is 128 pm. What is the density of copper metal? (Atomic mass of copper is 63.5) 

Answer 1

Given: Atomic radius of Cu atom 

 = 128 pm 

 = 128 x 10⁻¹⁰ cm 

 z = 4 (FCC) 

 Atomic mass of Cu = 63.5 

To find: Density of Cu (d) = ? 

Formula: i. Face diagonal 

Calculation: 

For FCC Lattice In face centred cubic arrangement face diagonal is four times the radius of atoms face diagonal.