1. DRILL Quiz … is the exact opposite of decomposition.
The molar mass of Ga(ClO3)3 is …

2. Objective The student will be able to:
Compare and contrast the empirical and molecular formula of a compound.

3. SAT/HSA ENRICHMENT
Which of these nitrogen fertilizers has the highest nitrogen content –ammonia [NH3], or urea [CO(NH2)2].

4. What is the difference b/w Empirical and Molecular Formulas?
Empirical Formulas
What is the difference b/w Empirical and Molecular Formulas?

5. Empirical Formulas
The empirical formula gives the lowest whole-number ratio of the atoms of the elements in a compound.
The empirical formula of a compound shows the smallest whole-number ratio of the atoms in the compound.

6. Empirical Formulas
Ethyne (C2H2) is a gas used in welder’s torches. Styrene (C8H8) is used in making polystyrene.
These two compounds of carbon have the same empirical formula (CH) but different molecular formulas.

7. Molecular Formulas
The molecular formula of a compound is either the same as its experimentally determined empirical formula, or it is a simple whole-number multiple of its empirical formula.

8. Molecular Formulas

9. Molecular Formulas
Methanal, ethanoic acid, and glucose all have the same empirical formula—CH2O.

10. Quick Quiz 2. Which of the following is NOT an empirical formula? NO2
H2N CH
C3H6

11. Quick Quiz
3. Determine the molecular formula of a compound that contains 40.0 percent C, 6.71 percent H, and percent O and has a molar mass of g.
C2H4O2
CH2O
C2H3O
C2H4O

12. Empirical Formula
Students will work together to complete an Empirical Formula worksheet.
10 min

13. Empirical Formula Determination
Empirical Formula Determination Lab
Purpose
To determine the empirical formula of Magnesium oxide.
55 min

14. Summary Did we accomplish the objective? Explain.
What information can you obtain from an empirical formula?
Compare and contrast molecular formula and empirical formula.

15. Summary
4. Which of the following molecular formulas are also empirical formulas?
Ribose (C5H10O5)
Ethyl butyrate (C6H12O2)
Chlorophyll (C55H72MgN4O5)
DEET (C12H17ON)

16. Homework
Empirical Formula Worksheet