Question

Three atoms P, Q and R crystallize in a cubic solid lattice where P atoms are at the alternate faces, R atoms are at the centre of edges and Q atoms are at the rd of the total corners present, hence the formula of the compound is

Answer 1

Answer:

Explanation:      P atoms are at corners. There are 8 corners and contribution of each corner is  

8

1

​  

. Therefore, total P atom is 8×  

8

1

​  

=1.

Q is at the centre of the cube. Therefore, total Q atom is 1.

R are present at the edges. There are 12 edges and contribution of each edge is  

4

1

​  

. Total R atoms are  

4

1

​  

×12=3. Formula is PQR  

3

​