The formula of a compound is _______in which atoms of elements B form hcp lattice and those of the element A occupy 2/3 rd of tetrahedral voids.

Explanation

To determine the formula of the compound where element B forms a hexagonal close-packed (hcp) lattice and element A occupies 2/3 of the tetrahedral voids, we can follow these steps:

### Step-by-Step Solution:

1. **Identify the number of atoms in the hcp lattice:**
- In a hexagonal close-packed (hcp) structure, there are 6 atoms of element B per unit cell.
- Therefore, \( Z_B = 6 \).

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