1. Physical and Chemical Changes AKS 11: Distinguish between a physical and chemical change

2. Concept of Change Matter: anything that has mass and volume Change: the act of altering a substance  Physical or Chemical

3. Physical Change Physical change: a change that occurs that does not change the identity of the substance. Does NOT result in the production of a new substance CAN be reversed easily by physical means

4. Can you think of ways I can make PHYSICAL changes to a piece of paper? Tearing Cutting Ripping/shredding Folding Gluing Writing on it

5. Physical Change Examples  Melting ice( change in state or phase)  Freezing Kool-aid  Tearing paper  Bending a wire Can you think of any more? Share with your elbow partner!

6. Chemical Changes CHEMICAL change: a change that occurs causing the identity of the substance to change DOES result in the production of a new substance CANNOT be reversed by physical means A chemical change is called a chemical reaction

7. Can you think of ways I can make chemical changes to a piece of paper? Burning it Pouring acid on it Eating it (digestion) – yuck!

8. Clues to a Chemical Change (Reaction) As I burn a piece of paper, can you think of up to 6 clues that tell us that a chemical change has taken place?

9. Clues to a Chemical Change Indicators of a chemical change: 1.Production of a gas 1.Fizzing, foaming, odor, bubbling 2.Production of energy (heat, light or sound) 1.Light given off, feels hot or cold, hear noise(s) 3.Temperature Change 1.Be careful with this one! 4.Unexpected Color change 1.Be careful with this one! 5.Production of a precipitate (solid) 1.Be careful with this one! 6.Production of a New Substance 1.Only if the atoms that make it up have been chemically altered! 2.The more of clues 1-5 you have, the more likely

10. Chemical Change Examples  Burning  Digesting food  Reacting with other substances Rusting, corroding, decomposing, tarnishing

11. Is it Physical or Chemical? ChangePhysicalChemical Melting cheese Burning wood Milk souring Wadding up paper Bicycle rusting

12. Indicators of chemical reaction What indicators do you observe? 2NI 3 ---  N 2 + 3I 2

13. Indicators of chemical reaction What indicators do you observe? C 12 H 22 O 11 + H 2 SO 4 ---  11H 2 0 + 12C

14. Indicators of chemical reaction What indicators do you observe? IO3− + 2H2O2 + CH2(COOH)2 + H+ → ICH(COOH)2 + 2O2 + 3H2O

15. Indicators of chemical reaction What indicators do you observe?