Question

An elements crystallizers in a cubic closed packed structure having FCC unit of an edge length $200$ pm. calculate the density if $200$g this elements contains $24\times {10}^{23}$ atoms.

Answer 1

For, FCC, given M$=200g$

z$=4$

N$=24\times {10}^{23}$ atoms

a$=200pm=200\times {10}^{-10}m=2\times {10}^{-8}cm$

Density is given by the equation,

$d=\frac{z\times N}{a^3\times N}=\frac{1000}{24}$

$\therefore d=41.67gc{m}^{-3}$