1. Elephant Toothpaste  Every table needs:  Trash bag  Glasses and gloves for each person  Bowl  Spoon  Once everyone is gloved and has their glasses on, send someone to Ms. Adabale to get:  ½ cup hydrogen peroxide in a bottle  Food coloring  Dish soap  2 tablespoons of warm water  Go to your table and wait for further instructions!

2. Decomposition of Hydrogen Peroxide  H 2 O 2 H 2 O + O 2 + heat

3. Catalyst  Which of the following is a chemical reaction? 1. rusting of iron 2. chopping wood 3. breaking a glass 4. mixing baking soda and vinegar 5. Shredding a piece of paper 6. baking a cake 7. crushing a can 8. melting an ice cube 9. mixing sand and water 10. cooking an egg 11. dissolving sugar and water 12. burning wood

4. Chemistry Mini-Lesson: Reactions & Catalysts  Chemical Reaction: process by which atoms or compounds are reorganized into different atoms/compounds.  Photosynthesis Reaction  6CO 2 + 6H 2 O + Light  C 6 H 12 O 6 + 6O 2 C C C C C C O O O O O O O O O O O O O O O O O O H H H H H H H H H H H H C C C C C C H H H H H H H H H H H H O O O O O O O O O O O O O O O O O O

5. Reevaluate your list! 1. rusting of iron 2. chopping wood 3. breaking a glass 4. mixing baking soda and vinegar 5. Shredding a piece of paper 6. baking a cake 7. crushing a can 8. melting an ice cube 9. mixing sand and water 10. cooking an egg 11. dissolving sugar and water 12. burning wood

6. Chemical Reactions  Clues that a chemical reaction has taken place:  Something new is visibly produced Example: baking a cake  A gas is created Example: baking soda and vinegar  Heat is given off or taken in Example: thermite reaction http://www.youtube.com/watch?v=o8gapa8ibK0

7. Reevaluate your list! 1. rusting of iron 2. chopping wood 3. breaking a glass 4. mixing baking soda and vinegar 5. Shredding a piece of paper 6. baking a cake 7. crushing a can 8. melting an ice cube 9. mixing sand and water 10. cooking an egg 11. dissolving sugar and water 12. burning wood

8. Reactants and Products  Photosynthesis Reaction:  6CO 2 + 6H 2 O + Light C 6 H 12 O 6 + 6O 2  The arrow always points from reactants to products. Reactants (Starting Substances) Products (Formed Substances)

9. Chemical Reactions 1. rusting of iron 2. chopping wood 3. breaking a glass 4. mixing baking soda and vinegar 5. Shredding a piece of paper 6. baking a cake 7. crushing a can 8. melting an ice cube 9. mixing sand and water 10. cooking an egg 11. dissolving sugar and water 12. burning wood

10. Activation Energy  Activation Energy: minimum amount of energy (usually heat) required to start a reaction. ***For both reactions, activation energy is measured from reactants to peak. Reaction Progress Energy Reactants Products XY X+Y Activation Energy Products can absorb energy Reaction Progress Energy Reactants Products XY X+Y Activation Energy Products can release energy Products that absorb energy feel COLD (endothermic) Products that release energy feel HOT (exothermic)

11. Chemistry Mini-Lesson: Reactions & Catalysts  If a reaction doesn’t get enough activation energy, it can’t start!  2 Options  Add more energy  Lower activation energy  Catalyst: Lowers activation energy of a chemical reaction resulting in a faster reaction rate Reaction Progress Energy Reactants Products XY X+Y Without Catalyst With Catalyst

12. Thinking Back…  What were the reactants?  What were the products?  Was the reaction endothermic or exothermic?  Was there a catalyst? If so, what?  How do you think changing the amount of hydrogen peroxide would alter the experiment? Yeast?