1. Chemists make useful substances in the lab using recipes.
Pharmaceutical Drugs
Plastics/ Petroleum Products

2. Useful things made from Sand using chemical recipes
Starting Materials
Final Product

3. Stoichiometry
Chemistry Recipes

4. Stoichiometry
Stoichiometry is the study of the relationship between the amounts of reactants and products in a chemical reaction
Stoichiometry provides RECIPES for chemical reactions.

5. Key Concept of Unit
The Coefficients of the balanced chemical equation represent the reacting ratios of particles (MOLES) of reactants and products.

6. Stoichiometry Problem Set HW 6-1
1) 2 Mg + O2 → 2 MgO video link

7. HW 6-1 , Problem #2
2) 2 H2 + O2 → 2 H2O video link

8. HW 6-1, #3
N2 + 3 H2 → 2 NH3

9. Stoichiometry Problem Set HW 7-1
4) 2 Mg + O2 → 2 MgO
atoms molecules molecules
A) 4 atoms + 2 molecules →
B) 8 atoms → 8 molecules
C) molecules →
4 molecules
4 molecules
20 atoms
20 molecules

10. HW 6-1, #5 molecules molecules molecules A) + 15 molecules →
5. N2 + 3 H2 → 2 NH3
molecules molecules molecules
A) molecules →
B) x →
molecules molecules molecules
C) 1 mole →
5 molecules
10 molecules
3(6.022 x 1023)
2(6.022 x 1023)
3 moles
2 moles

11. HW 6-1 , Problem #6 2) 2 H2 + O2 → 2 H2O 2 A) 2 moles + moles → moles
B) moles + 4 moles → moles
C) moles moles → moles 1 2 8 8 10 5

12. Quantities in a Balanced Chemical Equation

13. Use mole bridge for more complex ratios HW 7-1, #7A
4 NH O2 → 4 NO2 + 6 H2O
? Moles moles
10.0 moles O2 ( ) 4
moles NH3 7
moles O2
Answer: 40/7 = (3 SF, matches given)

14. Use mole bridge for more complex ratios HW 7-1, #7B
4 NH O2 → 4 NO2 + 6 H2O
11.5 moles ? Moles
11.5 moles NH3 ( )
6 moles H2O
4 moles NH3
Answer: = (3 SF, matches given)

15. Use mole bridge for more complex ratios HW 7-1, #7C
4 NH O2 → 4 NO2 + 6 H2O
? Moles 8.6 moles
8.6 moles H2O ( )
4 moles NO2
6 moles H2O
Answer: = (2 SF, matches given)

16. Use mole bridge for more complex ratios HW 7-1, #7D
4 NH O2 → 4 NO2 + 6 H2O
9.2 moles ? Moles
9.2 moles O2 ( )
6 moles H2 O
7 moles O2
Answer: = (2 SF, matches given)