The empirical formula of the compound is XY₃.
Calculate the mass ratio of X and Y:
Let the total mass of the compound be 100 grams.
Then, mass of X = 40% of 100 grams = 40 grams.
Mass of Y = 60% of 100 grams = 60 grams.
Therefore, the mass ratio of X to Y is 40:60 or 2:3.
Convert mass ratio to mole ratio:
We need to know the atomic masses of X and Y. Since the atomic mass of X is twice that of Y, let Y's atomic mass be Y = 1. Then, X's atomic mass is X = 2Y = 2.
Divide both sides of the mass ratio (2:3) by the atomic mass of Y (1) to get the mole ratio:
X:Y = 2/1 : 3/1 = 2:3.
Write the empirical formula:
The empirical formula shows the simplest whole number ratio of atoms in a compound.
Therefore, the empirical formula for the compound is XY₃, where X represents two atoms of element X and Y represents three atoms of element Y.
Complete Question:
The elements X and Y form a compound that is 60% X and 40% Y by mass. The atomic mass of X is twice that of Y. What is the empirical formula of the compound?