Q. In a compound, atoms of element $Y\$form ccp lattice and those of element X occupy 2/3rd of tetrahedral voids. The formula of the compound will be
A) $X_{4}Y_{3}$
B) $X_{2}Y_{3}$
C) $X_{2}Y$
D) $X_{3}Y_{4}$
Explanation
(a)
Suppose atoms of element Y in $ccp$
= 100
Number of tetrahedral voids $= 2 \times 100$
Number of atoms of element $X = \frac{2}{3} \times 200$
$\ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ = \frac{400}{3}$
$\ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \frac{X}{Y} = \frac{400}{300}$
Formula $\ = X_{4}Y_{3}$
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.