What is the mass of bcc type unit cell of sodium if mass of one atom of sodium is $3 \cdot 819 \times…
What is the mass of bcc type unit cell of sodium if mass of one atom of sodium is $3 \cdot 819 \times 10^{-23} \mathrm{~g}$ ?
$7 \cdot 038 \times 10^{-23} \mathrm{~g}$
$7 \cdot 638 \times 10^{-23} \mathrm{~g}$
$3 \cdot 819 \times 10^{-23} \mathrm{~g}$
$1.5276 \times 10^{-22} \mathrm{~g}$
Solution
No. of atoms per bcc type of unit cell, $\mathrm{n}=2$
Mass of bcc unit cell $=$ Mass of two atoms
$\begin{aligned} \therefore \text { Mass of bcc unit cell of } \mathrm{Na} &=3.819 \times 10^{-23} \times 2 \\ &=7.638 \times 10^{-23} \mathrm{~g} \end{aligned}$