Question

The unit cell of copper corresponds to a face centered cube of edge length $3.596\mathring{A}$ with one copper atom at each lattice point. The calculated density of copper in $kg/m^3$ is _________. [Molar mass of $Cu=63.54g$ ; Avogadro's number $=6.022\times 10^{23}$ ] (Round off answer to nearest integer value).

Answer 1

Answer: 9076

Given:
$a=3.596\mathring{A}$
$d=\frac{Z\times M}{N_A\times a^3}$
$d=\frac{4\times 63.54\times {\left(10\right)}^{-3}}{6.022\times {\left(10\right)}^{23}\times {\left(3.596\times {\left(10\right)}^{-10}\right)}^3}$
$d=0.9076\times 10^4=9076kg/m^3$