Question

In $ABC$ packing if the number of atoms in the unit cell is $n$ then the number of tetrahedral voids in the unit cell is equal to:

• A. $n$
• B. $\frac{n}{2}$
• C. $\frac{n}{4}$
• D. $2n$

Answer 1

The correct option is D $2n$

In a closed packed structure, the number of tetrahedral voids in a single unit cell is twice the number of octahedral voids.

number of octahedral voids = number of atoms

So for $n$ atoms, the number of tetrahedral voids will be $2n$.

Hence, the correct answer is option "D".