Question

A compound $AB$ has simple cubic structure and has molecular mass $99$. Its density is $3.4g{cm}^{-3}$. What will be the edge length of the unit cell?

Answer 1

Simple cubic structure molecular mass $=99$
$\rho =3.4g/{cm}^3$
Edge length $=$?
$\rho =\frac{Z\times M}{a^3\times N_A}g/{cm}^3$

$3.4=\frac{1\times 99}{a^3\times 6.023\times {10}^{23}}$

$a^3=\frac{99}{3.4\times 6.023\times {10}^{23}}$

$a=3.6\times {10}^{-8}cm$