Question

A solid is made of two element P and Q. Atoms P are in ccp arrangement and atoms Q occupy all the octahedral voids and half of the tetrahedral voids, then the simplest formula of the compound is

(a) PQ₂ 

(b) P₂Q 

(c) PQ 

(d) P₂O₂

Answer 1

Correct Option (a) PQ₂ 

Explanation :

Four atoms P contributes to one unit cell from ccp arrangement and 4 atoms Q from the all octahedral voids and 4 atoms Q from the half of the tetrahedral void contributes one unit cell. So, formula of solid is P₄O₈ so, the simplest formula of the solid is PQ₂.