 
       
      
    An element having an atomic radius of 0.14 nm crystallizes in an fcc unit cell. What is the length of a side of the cell ?
0.56 nm
0.24 nm
0.96 nm
0.4 nm
 
                
                  For fcc unit cell, 
Here, a is the edge length and r is the atomic radius (0.144 nm).
Hence, the length of a side of a cell is 0.407 nm.
 
                