Silver forms ccp lattice and X-ray studies of its crystal show that the edge length of its unit cell is 408.6 pm. Calculate the density of silver (Atomic wt. = 107.9u).

4 views

1 Answers

Solution :

Silver forms cubic close packing (ccp) , therefore the number of silver atoms per unit cell z=4

Molar mass of silver M=107.9 gmol−1 = 107.9×10−3kgmol−1

Edge length of unit cell a=408.6 pm = 408.6×10−12

Density d=(z.M)/(a3.NA)

d=4×(107.9×10−3kgmol−1)/(408.6×10−12m)3(6.022×1023mol−1)

=10.5×103kgm−3

d=10.5gcm−3

4 views