Question

a crystalline solid forming cubic lattice is made of two elements A and B atoms of A are present at corner and atom of B at face centres of all along one of the body diagonal are missing then the simplest formula of the solid is​

Answer 1

Answer:

ANSWER

Number of atoms of X in fcc packing (at corners and face centres of cubic unit cell) =8×

8

1

+6×

2

1

=4

Number of atoms of Y at octahedral voids =4

Along one body diagonal there are two X atoms and one Y atom.

Number of effective atoms of X after removal

=4−2×

8

1

=

4

15

Number of effective atoms of Y after removal =4−1=3

X:Y=

4

15

:3

=5:4

∴ Simplest formula =X

5

Y

4