Q. The ratio of close packed atoms to tetrahedral holes in cubic close packing is
A) 1:1
B) 1:2
C) 1:3
D) 2:1
Explanation
(b)
Every constituent has two tetrahedral voids. In ccp lattice atoms
$= 8 \times \frac{1}{8} + 6 \times \frac{1}{2} = 4$
$\therefore$ tetrahedral voids $= 4 \times \ 2 = 8$
Thus, ratio $= 4\ :8 = 1\ :2$
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.