1. UNIT 1 M ATTER D AY 8 S EPTEMBER 12, 2016 Chemical Changes of Matter 8 th Grade Science

2. S EPTEMBER 12, 2016 Science Starter: When you heat a substance, what 2 things happen to its molecules (particles)? And, NO, you cannot say they get warmer Remember to correct your answer or add notes as we discuss. ALSO, Take out your homework and yellow vocab. sheet, too.

3. S EPT. 12, 2016 Plan for today: 1. Science Starter 2. E. Q. 3. Discuss tonight’s homework 4. Review Friday’s homework 5. Review effects of temperature on density -Hands-on activity -Discussion -Video-How lava lamps work 6. Lesson – Chemical Change -Notes -Observations -Video 7. Practice activity- “Two Ways to Change” 8. Wrap-up

4. Copy on Page 9 Essential Question -How are chemical changes different from physical changes?

5. Homework: 1.Flash cards #14-17 and yellow vocab. sheets are due Wednesday. (Weds. is the last day to turn in #6- 13 for half credit.) 2.Complete the “Two Ways to Change” wkst. if we don’t finish it in class today-due tomorrow. 3.CFA Wednesday over physical and chemical properties and physical and chemical change. Study flash cards. Be sure you know the formulas for density, mass, volume and how water displacement works to find volume.

6. CFA MINIMUM SCORE REQUIREMENT The minimum score to show proficiency (that you know the content pretty well) is 80%. If you score 80% or higher on the CFA, you have met the minimum requirement for this section on matter. If you score below 80%, you will be required to take a follow-up quiz on Friday (that is longer than the CFA) after I do some review and remediation with the class on Thursday. If you scored 80% or higher and would still like to take the quiz, you may. The higher of the 2 grades will go in the gradebook. Therefore, it would be a really good idea to study over the specific physical and chemical properties we have discussed, as well as what makes physical changes different from chemical changes.

7. Let’s talk a little more about the effects of temperature on the physical property of density. Take the pieces of paper out of your baggie and lay them out on your desk so that they are pretty close together. Wait for further instructions.

8. Let’s apply this principle of temperature and density to how a lava lamp works. How a lava lamp works

9. Take out Friday’s homework sheet – Physical vs. chemical properties and let’s review it.

10. R EVIEWING P HYSICAL C HANGE … A PHYSICAL change does not result in a new substance being formed. It only changes the appearance of a substance. Ex. Melting ice – Solid water Liquid water It’s still water!!!!! Ex. Shaping a gold bar into jewelry It’s still gold!!!!

11. 18. C HEMICAL CHANGE Def. - a CHANGE that happens when two or more substances combine (react with one another) and form a new, different substance AD – the composition/identity of the matter is changed AD – the new substances have new properties (iron is magnetic but rust…the new substance, is NOT magnetic) Ex: milk souring, apples browning, baking a cake, fireworks, copper turning green (oxidizing), nail rusting, wood burning

12. ANOTHER EXAMPLE OF HOW A C HEMICAL CHANGE PRODUCES NEW SUBSTANCES WITH DIFFERENT PROPERTIES … Sodium and chlorine are elements on the periodic table of elements. They are very reactive and combine easily with one another. Sodium is a silvery metal that is soft enough to be cut with a knife. Chlorine is a greenish-yellow poisonous gas. When sodium and chlorine react with one another, they produce SALT. Salt is NOT silvery or soft, it is NOT greenish-yellow, it is NOT poisonous, and it is NOT a gas.

13. L ET ’ S WATCH A VIDEO TO HELP US BETTER UNDERSTAND CHEMICAL CHANGES ! Video on chemical changes

14. Signs of a Chemical Change: distinct color change, odor produced, energy in the form of heat or light, bubbling or fizzing, the formation of a precipitate indicate a chemical change has occurred. Ex: Fireworks; When baking a cake, odor, browning and air pockets in the cake indicate a chemical change occurred. A gas is produced. This is why cake is spongy.  Precipitate: the cloudy solid that results when two liquid substances are combined.

15. RECAP- PHYSICAL VS. CHEMICAL CHANGES Physical changes don’t change the composition/identity of the substance, only its appearance or form. Chemical changes always result in NEW substances with different properties. Composition: the type of matter making up a substance and how matter is arranged in the substance.

16. L ETS ’ SEE HOW WELL WE ’ RE CATCHING ON TO PHYSICAL VS. CHEMICAL CHANGES! ½ page handout “Two Ways to Change” Work cooperatively with your group to identify each situation as a physical or a chemical change. 3 minutes. GO!

17. Wrap-up: Answer today’s E.Q.