1.  Write the chemical equation and answer the following questions: CH 4 + 2 O 2 → CO 2 + 2 H 2 O 1. What are the numbers called and what do they tell us about the equation? 2. Write down the compounds that appear on the reactant side? 3. Write down the compounds that appear on the product side? 4. What does the arrow represent in the above chemical equation? 5. What are the small numbers called in the above equation and what do they tell us about the chemical formula?

3.  SWBAT define and balance combustion reactions.

4.  Today we will be working with flames. This means we must exercise caution and maturity.  Safety Procedures

5.  Combustion Reaction – occurs when a hydrocarbon (compound made up of hydrogen and carbons) reacts with oxygen  Usually produces Carbon dioxide (CO 2 ) and water (H 2 O)

6. C 3 H 8 + O 2 → CO 2 + H 2 O propane oxygen carbon dioxide water reactants products 3 :C: 1 8 :H: 2 2 :O: 3

7. Since oxygen is located in 2 different places on the product side this should be the atom you balance LAST. Fix hydrogen and carbon first before you move on to oxygen. What law does balancing follow??? Law of Conservation of Mass

8. Reactants:Products: C: H: O:

10. 1. What type of molecule is C 3 H 8 ? 1. Name C 3 H 8 : 2. Draw the structure of C 3 H 8

11. Hint: What is always produced from a combustion reaction? ___C 2 H 4 + ___O 2  ___+___ Reactants Products

12.  What are the 2 products always formed in a combustion reaction?  Name & draw the hydrocarbon C 2 H 4 :

13.  Combustion is considered a chemical change.  Fire/Burning flame are general signs that a combustion reaction is taking place.  An incomplete combustion reaction happens when there is not enough oxygen in the reactants and produces CO instead of CO 2

14. Properties of Oxygen: Properties of Carbon Dioxide: Colorless/odorless gas Very reactiveExtinguishes flame Covalently bondsCovalent Compound

15. Work time

16. 1. Name the two products that are usually formed from a combustion reaction. 2. Balance the combustion reaction: 3. ___C 2 H 4 + ___O 2  ___H 2 O + ___CO 2 4. What reactants are usually present when we are given a combustion reaction?