1. Chemical Reactions The story

2. Hi there. This is H 2 O. So is this. Meet 2H 2 O

3. They weren’t always so happy.

4. Hmph. You’re out of control Bbbllgghh!!

5. You need me. I’m important. Meet O 2

6. He’s light. He’s fast. He’s crazy! Meet H 2 B-b-b-b-b

7. One day… Hey! Quit it!

8. One day…

9. Chemical Reactions Bonds are broken and new bonds are formed. Bonds in H 2 & O 2 break.

10. Chemical Reactions Bonds are broken and new bonds are formed. New bonds form.

11. Chemical Reactions New substances are formed. 2 gases react Water is formed

12. Parts of a Reaction Reactants: The chemicals you have before the reaction H 2 That’d be us. Tbtbbhth! Tbtbbhth! H 2 O 2

13. Parts of a Reaction Products: The substances created in the reaction H 2 O H 2 O

14. Chemical Equation Reactants Products Parts of a Reaction

15. Chemical Reactions During chemical reactions atoms are not created or destroyed. They’re just rearranged. 2 oxygen atoms 4 hydrogen atoms 2 oxygen atoms 4 hydrogen atoms

16. How can you tell if a chemical reaction has happened? Let me give you some hints.

17. Is it a chemical reaction? If a gas is produced it might be a chemical reaction. Look for the bubbles!

18. Is it a chemical reaction? If it changes color it might be a chemical reaction. Like iron rusting!

19. Is it a chemical reaction? If it gets hotter it might be a chemical reaction.

20. Is it a chemical reaction? Or…if it gets colder it might be a chemical reaction.

21. Exothermic Reactions Exothermic reactions release energy. These reactions feel hot.

22. Endothermic Reactions Endothermic reactions absorb energy. These reactions feel cold.

23. Image Sources Water Molecule http://commons.wikimedia.org/wiki/File:Water-3D-vdW.png Oxygen and Hydrogen Molecules http://en.wikipedia.org/wiki/File:Nitrogen-3D-vdW.png POW! http://www.scribbleonwalls.com/images/products/comc_05.jpg Shiny Can http://www.flickr.com/photos/99347433@N00/315475438/ Rusty Can http://www.flickr.com/photos/25149679@N00/466492041/ Burning Match http://www.flickr.com/photos/8070463@N03/3069201840/ Icicles http://www.flickr.com/photos/14316700@N08/3075538662/ Bonfire http://www.flickr.com/photos/dominicspics/1902322480/ Icy branches http://www.flickr.com/photos/laszlo-photo/426155665/