Answer
The empirical formula for the compound is K₂SO₄
Step-by-step explanation
Given:
% composition: 44.9% K, 18.4% S, and 36.7% O
What to find:
The empirical formula for the compound.
Step-by-step solution:
Assume we have 100 grams total of the substance.
Grams K = 44.9/100 x 100 g = 44.9 grams
Grams S = 18.4/100 x 100 g = 18.4 grams
Grams O = 36.7/100 x 100 g = 36.7 grams
The next step is to convert the number of grams of each element into moles as shown below using the molar masses of O = 15.999 g/mol, S = 32.065 g/mol, and K = 39.0983 g/mol.
Note: Mole = Mass/Molar mass
Moles K = 44.9g/39.0983 g/mol = 1.15 mol
Moles S = 18.4g/32.065 g/mol = 0.57 mol
Moles O = 36.7g/15.999 g/mol = 2.29 mol
The final step is to divide the number of moles of each element by the smallest number obtained:
K = 1.15/0.57 = 2
S = 0.57/0.57 = 1
O = 2.29/0.57 = 4
Therefore the empirical formula for the compound is K₂SO₄