Chemical Properties & Physical and Chemical Changes

1. Warm-UpSit down and complete the Phase Change Graph worksheet. Once you and your table-partner are finished, quietly share your answers with each other and be prepared to discuss with the class.

2. Chemical Properties & Physical and Chemical Changes

3. Standard – • S8P1. Students will examine the scientific view of the nature of matter. • d. Distinguish between physical and chemical properties of matter as physical (i.e., density, melting point, boiling point) or chemical (i.e., reactivity, combustibility).

4. Essential Question: How can the physical and chemical properties of a substance be used to determine its identity?

5. Physical changes are those changes that do not result in the production of a new substance.  If you melt a block of ice, you still have H2O at the end of the change.   

6. If you break a bottle, you still have glass.  Painting your nails will not stop them from being fingernails.  Some common examples of physical changes are: melting, freezing, condensing, breaking, crushing, cutting, and bending.

7. Some, but not all physical changes can be reversed. You could refreeze the water into ice, but you cannot put your hair back together if you don’t like your haircut!

8. CHEMICAL PROPERTIES Chemical properties can ONLY be observed AS the substances are changing into different substances.

9. Chemical changes, or chemical reactions, are changes that result in the production of another substance. 

10. FLAMMABILITY: A material’s ability to BURN in the presence of OXYGEN

11. REACTIVITY:How readily (easily) a substance combines chemically with other substances.

12. Which has higher reactivity? A 14 karat gold ring or a cheap metal ring from the vending machine at the grocery store? What is your evidence?

13. When you burn a log in a fireplace, you are carrying out a chemical reaction that releases carbon.  When light and carbon dioxide are used in photosynthesis, you are carrying out a chemical reaction that produces water and oxygen. 

14. Common examples of chemical changes that you may be somewhat familiar with are; digestion, respiration, photosynthesis, burning, and decomposition. 

15. Physical or Chemical Change? • Painting Wood • PHYSICAL

16. Physical or Chemical Change? • Burning Paper • CHEMICAL

17. Physical or Chemical Change? • Digestion of food • CHEMICAL

18. Physical or Chemical Change? • Sugar dissolving in water • PHYSICAL

19. Physical or Chemical Change? • Evaporation • PHYSICAL

20. Physical or Chemical Change? • A pond freezing in winter • PHYSICAL

21. Physical or Chemical Change? • Melting ice • PHYSICAL

22. Physical or Chemical Change? • Fireworks exploding • CHEMICAL

23. Physical or Chemical Change? • Cutting wire • PHYSICAL

24. Physical or Chemical Change? • Painting fingernails • PHYSICAL

25. Physical or Chemical Change? • Metal corroding • CHEMICAL

26. Physical or Chemical Change? • Cutting fabric • PHYSICAL

27. Physical or Chemical Change? • Baking muffins • CHEMICAL

28. Physical or Chemical Change? • Shattering glass • PHYSICAL

29. Physical or Chemical Change? • Decomposition of old leaves • CHEMICAL

30. Physical or Chemical Change? • Wrinkling a shirt • PHYSICAL

31. Physical or Chemical Change? • An old nail rusting • CHEMICAL

32. Physical or Chemical Change? • Meat spoiling • CHEMICAL

33. Physical or Chemical Change? • Melting rock into lava • PHYSICAL

34. Physical or Chemical Change? • Hardening/cooling lava into rock • PHYSICAL

35. Physical or Chemical Change? • Melting plastic • PHYSICAL

36. Physical or Chemical Change? • Burning plastic • CHEMICAL

37. Physical or Chemical Change? • Making plastic • CHEMICAL