Question

Q5) in a crystalline solid , anions 'C' are arranged in cubic close packing cations 'A' occupy 50%of tetrahedral voids and cations 'B' occupy 50% of octahedral voids .what is the formula of the solid

Answer 1

In a ccp arrangement, number of atom per unit cell = 4

So, number of anions, C = 4

Number of tetrahedral voids = 8

Number of A atoms in tetrahedral voids = (50/100) x 8 = 4

Number of octahedral voids = 4

Number of B atoms in octahedral voids= (50/100) x 4 = 2

Hence, the formula of the solid = A4B2C4