In a newly synthesized compound, atoms of element Y form a cubic close-packed (ccp) lattice. Atoms o — Solid State Chemistry Question

💡 Solution & Explanation

Y forms the CCP lattice, meaning there are effectively 4 atoms of Y per unit cell. The total number of tetrahedral voids is $2 \times 4 = 8$. X occupies $\frac{2}{3}$ rd of them, so number of X atoms = $8 \times \frac{2}{3} = \frac{16}{3}$. The ratio X : Y is $\frac{16}{3} : 4 = 16 : 12 = 4 : 3$. Thus, the formula is $X_4Y_3$.