Q. A compound of ‘A’ and ‘B’ crystallises in a cubic lattice in which ‘A’ atoms occupy the lattice points at the corners of the cube. The ‘B’ atoms occupy the centre of each face of the cube. The probable empirical formula of the compound is
A) $AB_{2}$
B) $A_{3}B$
C) $AB$
D) $AB_{3}$
Explanation
(d)
A occupies corners, thus number of A atoms per unit cell
$= 8 \times \frac{1}{8} = 1$
B occupies face centres, thus number of B atoms per unit cell
$= 6 \times \frac{1}{2} = 3$
$\therefore$ The empirical formula of the compound is $AB_{3}.\$
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.