Chemistry - Solid State Question with Solution | TestHub

The mass of one unit cell is given by the product of its density and volume:

Mass of unit cell $=\rho \times a^3=6\cdot 6\times 10^{-22}\text{ g}$

For a body-centered cubic (bcc) crystal structure, the number of atoms per unit cell is $Z=2$.

Mass of one atom $=\frac{\text{Mass of unit cell}}{Z}=\frac{6\cdot 6\times 10^{-22}}{2}=3\cdot 3\times 10^{-22}\text{ g}$

The number of atoms in $1\text{ g}$ of the metal is:

Number of atoms $=\frac{1\text{ g}}{\text{Mass of one atom}}=\frac{1}{3\cdot 3\times 10^{-22}}=3\cdot 03\times 10^{21}$

Answer: $3\cdot 03\times 10^{21}$