Paper: CSIR-NET June 2014 · Subject: Physical Chemistry · Chapter: Solid State Chemistry · Topic: Solid State Chemistry – General · Marks: 2 · Difficulty: Medium
A compound $\mathrm{A}_{\mathrm{x}} \mathrm{B}_{\mathrm{y}}$ has a cubic structure with A atoms occupying all the corners of the cube as well as all the face center positions. The B atoms occupy four tetrahedral voids. The values of x and y respectively, are
(a)4, 4
(b)4, 8
(c)8, 4
(d)4, 2
Answer
Answer: A ✓ checked by 4AB · confidence high
Explanation
A at corners and face centres = 4 per cell; B in four of the eight tetrahedral holes = 4: A₄B₄, i.e. x = y = 4 (zinc-blende type).