Question

In an FCC unit cell a cube is formed by joining the centers of all the tetrahedral voids to generate a new cube.Then the new cube would contain voids as :

$\square$

• A. 1 full Tetrahedral void, 1 full Octahedral void
• B. 1 full Tetrahedral void only
• C. 8 full Tetrahedral voids and 1 full Octahedral void
• D. 1 full Octahedral void only

Answer 1

Answer: (A)

1 full Tetrahedral void, 1 full Octahedral void

Answer 2

No. of tetrahedral voids = 8 × $\frac{1}{8}$= 1

No. of Octahedral voids = 1×1 = 1 (at body center).