Question

4. In a compound X atoms are at all corners of a cubic unit cell, Y atoms occupy 1/2 of face centres, Z atoms are at all edge centres & atom M is at body centre. what is the formula of the solid? (Ans. X2Y3Z6M2)​

Answer 1

Since atom X is present at corner and one comer is shared by eight unit cells, number of X atoms per unit cell

Atom Y is present at body centred position and used by only one unit cell. So, number of Y atoms per unit cell = 1 Atom Z is present at the centre of each face, so shared by two unit cells, thus number of Z atoms per unit cell

Hence, the formula of compound