1) In a compound, atoms of element Y form ccp lattice and those of element X occupy 2/3rd of tetrahedral voids. The formula of the compound will be A) $X_{4}Y_{3}$ B) $X_{2}Y_{3}$ C) $X_{2}Y$ D) $X_{3}Y_{4}$ Answer: Option AExplanation:From the given data, we have Number of Y atoms in a unit cell = 4 Number of X atoms in a unit cell = 8×2/3 = 16/3 From the above we get the formula of the compound as X16/3Y4 Or X4 Y3
