An element with atomic mass 60 having fcc structure has a density of `6.23 "g/cm"^3`.What is the edge length of unit cell ?

Options

A. 300 pm
B. 250 pm
C. 400 pm
D. 160 pm

Answer

C

Explanation

`d = (Z xx M)/(a^3 xx N_A)`
`6.23 = (4 xx 60)/(a^3 xx 6.02 xx 10^(23))`
`a^3 = (4 xx 60)/(6.23 xx 6.02 xx 10^(23))`
`a = 4 xx 10^(-8) cm = 400 " pm " `.