Question

In a compound, atoms of B form hcp lattice and atoms of A occupy 2/3rd of octahedral voids and half of tetrahedral voids. Write the formula of the compound.

Answer 1

Dear student,

In hcp lattice,

the no. of tetrahedral voids formed is equal to twice the no. of atoms of element which forms the lattice and octahedral void is equal to the number of atoms.

i.e. Tetrahedral voids = 2N (No. of atoms of B)
So the no. of atoms of A present in tetrahedral void = 2/3+1/2 = 7/6

Hence ratio of A:B = 4/3 :1 = 7:6

Hence formula = A₇B₆

Regards