1. Empirical/Molecular Notes

2. Empirical Formula
A formula giving the proportions of the elements present in a compound but not the actual numbers or arrangement of atoms.
Calculate the ratio of moles of each element in the compound
Smallest whole number ratio becomes the subscripts

3. Determine the empirical formula for compound that has the following analysis:
66.0% barium and 34.0% chlorine BaCl2

4. A 0. 858g sample of an unknown substance is composed of 0
A 0.858g sample of an unknown substance is composed of 0.537g copper and 0.321g fluorine. CuF2

5. 60.9% As and 39.1% S As2S3

6. Determine the empirical formula for compounds that have the following analyses:
80.38% bismuth, 18.46% oxygen, 1.16% hydrogen BiO3H3
12.67% aluminum, 19.73% nitrogen, and % oxygen AlN3O9

7. Molecular Formula
a chemical formula based on analysis and molecular weight
Multiple of empirical formula
Need both molar mass (experimental mass) and empirical formula to find
Find empirical first if not given

8. Determine the molecular formulas for compounds having the following empirical formulas and molar masses:
C2H4S; experimental mass C6H12S3

9. 41.39% carbon, 3.47% hydrogen, and 55.14% oxygen; experimental molar mass 116.07 C4H4O4

10. C2H3O2; experimental molar mass 119 C4H6O4
54.53% Carbon, 9.15% hydrogen, and 36.32% oxygen; experimental molar mass 88 C4H8O2