1. DAILY QUESTION
November 3, 2008
What does the law of definite proportions state?

2. Agenda 11/3/08 Practice with balancing equations and using mole ratios
Daily Question
Check-in: Balancing Equations Wksht
Ch 6 Sect 3 Notes
Determining Mole Ratios
Practice with balancing equations and using mole ratios
Assignments: Ch 6 Sect 3 Review Worksheet due 11/4

3. The law of definite proportions
A compound always contains the same elements in the same proportions, regardless of how the compound is made or how much of the compound is formed

4. The mole ratio
The mole ratio for any reaction comes from the balanced chemical equation
2H20 → 2H2 + O2
2 mol: 2 mol: 1mol

5. Using mole ratios 2H2O → 2H2 + O2
If you start with 2 mol of water, how many moles of hydrogen gas are produced?
2 mol

6. Using mole ratios 2Mg + O2 → 2MgO
If you start with 5 mol of O2, how many moles of Mg will you need?
10 mol of Mg