Question

give
the formula of unit cell when A
occupy Hcp
B. Is at Tetrahedral void, O at
octerhedsal void
​

Answer 1

Explanation:

Given that, atoms of B forms hcp lattice. So, the atoms at corners are shared by 6 unit cells. So, its contribution is

6

1

; Face centered atoms contribute

2

1

and middle layer atoms contribute 1 each.

So, effective number of atoms in unit cell =

6

1

×12+

2

1

×2+1×3

=2+1+3=6

Number of tetrahedral voids =2× Number of atoms forming the lattice.

=2×6=12

So, number of atoms of A=

3

2

×12=8

Number of atoms of B=6

So, A:B⇒A:B

8:6 4:3

So, formula is A

4

B

3

Answer 2

Answer:

A2b4o2 is the formula of the compound