1. Empirical & Molecular Formulas
Empirical Formulas
Smallest, whole # ratio of atoms in a molecule
Ex: NaCl, H2O, C12H22O11
not necessarily the actual formula for the compound
Ex: CH2O  C6H12O6
Molecular Formulas
Actual formula for the compound

2. Empirical & Molecular Formulas
Ex 1: Determine the empirical formula of the compounds with the following composition by mass: 10.4% C, 27.8% S and 61.7% Cl

3. Empirical & Molecular Formulas
Ex 2: Determine the empirical formula of the compounds with the following composition by mass: 21.7% C, 9.6% O and 68.7% F.

4. Empirical & Molecular Formulas
Ex. 3: Give the empirical formula of each of the following compounds if a sample contains:
40.0% C, 6.7% H and 53.3% O by mass.

5. Empirical & Molecular Formulas
Ex. 4: Give the empirical formula of each of the following compounds if a sample contains:
11.66g Iron and 5.01g Oxygen

6. Empirical & Molecular Formulas
Ex. 5: What is the molecular formula of each of the following compounds?
empirical formula CH
molar mass = 78 g/mol

7. Empirical & Molecular Formulas
Ex. 5: What is the molecular formula of each of the following compounds?
empirical formula CH
molar mass = 78 g/mol

8. Empirical & Molecular Formulas
When the hydrated form of Li2SiF6 is heated, its mass decreases of to g. Determine the formula for the hydrate, and name the hydrate.

9. Empirical & Molecular Formulas
When the hydrated form of Li2SiF6 is heated, its mass decreases of to g. Determine the formula for the hydrate, and name the hydrate.