Question

Na and Mg crystallize in bcc and fcc-type crystals, the ratio of the number of atoms present in the unit cell of their respective crystal is:

• A. $1:3$
• B. $1:2$
• C. $3:2$
• D. $4:1$

Answer 1

The correct option is B $1:2$

As we know, bcc have $2$ atoms/unit while fcc have $4$ atoms/unit and so, their ratio is $\frac{2}{4}=\frac{1}{2}$

Hence, the correct option is $\text{B}$