1. WUP#21
Which is an empirical formula (E.F.) and which is a molecular formula(M.F.)? 1. H2O 2. C4H10 3. CO2 4. CH2O 5. C6H12O6

2. Empirical Formulas
from Percents and Mass

3. Empirical Formula
Definition: A formula that shows the simplest whole-number ratio of the atoms in a compound
Ex: H2O
Not an Ex: H4O2

4. Chemical Formula from % or mass
Percent to mass, Mass to mole, Divide by small, Multiply 'til whole.

5. Empirical formula from Percent #1
Determine the empirical formula for a compound with the percent composition of 40.00% carbon, 6.72% hydrogen, and 53.28% oxygen.

6. Empirical formula from Percent #2
Determine the empirical formula for methyl acetate, which has the following chemical analysis:
48.64% carbon, 8.16% hydrogen and 43.20% oxygen.

7. Empirical formula from mass #3
A 50.0 g sample of a compound contains g Na, g O, and g S. Determine the empirical formula.

8. Empirical formula from mass #4
A 50.0 gram sample contains
2.52 grams of Be, 5.01 g Al, g Si, and g O.
Determine the empirical formula.