1. Science 104- Monday October 6 th Schedule Starter Attendance Return graded assignments Lesson on pH Memory Questions Discussion on pH lab Schedule Starter Attendance Return graded assignments Lesson on pH Memory Questions Discussion on pH lab Learning Intentions To relate acids and bases to the pH scale To understand that substances in nature have different pH values

3. Learning Curve

4. Classroom Routines Starters Vocabulary Quizzes Class website Missing Class Participation Starters Vocabulary Quizzes Class website Missing Class Participation

5. Starter Copy down the following definitions Acid: A substance with a pH of less than 7. Vinegar and lemons are acidic substances with a sour taste. (page 467) Base: A substance with a pH of more than 7. Baking soda is an example of a base with a bitter taste. (page 467) pH: A scale that classifies substances according to their acidity and alkalinity. (page 190)

6. Word Association When I say a word write down the first three words that come to mind. READY SET WORD: FIRE READY SET WORD: ACIDS

8. Acids and Bases Acids and bases are two special kinds of chemicals Almost all liquids are either acids or bases to some degree. Whether a liquid is an acid or a base depends on the ions that are present When acids and bases mix they neutralize (cancel) each other

9. In Our Bodies Stomach releases hydrochloric acid to help breakdown food Heartburn is when the acid comes up the esophagus Stomach is protected by thick lining Food exiting the stomach is mixed with strong bases

10. In Nature Bee stings -Injects you with an acid -Causes pain and swelling Bee stings -Injects you with an acid -Causes pain and swelling Poison Ivy -Produce a basic substance - Severe irritation occurs Poison Ivy -Produce a basic substance - Severe irritation occurs

11. What should you do? Page 188 Textbook Apply a basic substance like baking soda Apply an acidic substance like vinegar or lemon

12. In Food Acids -Sour Taste -Used for flavouring Acids -Sour Taste -Used for flavouring Bases -Bitter Taste Bases -Bitter Taste

13. In The Environment Acid Rain -Damages buildings -Effects plants -Can change the acidity of lakes http://www.ecokids.ca/P UB/eco_info/topics/fro gs/acid_rain/play_acidl ake.cfm Acid Rain -Damages buildings -Effects plants -Can change the acidity of lakes http://www.ecokids.ca/P UB/eco_info/topics/fro gs/acid_rain/play_acidl ake.cfm

14. How do we know which is which? One is an acid, one is a base and one is neutral.

15. Litmus Paper Blue Litmus Paper Red Litmus Paper Acidic Substance Turns RedStays Red Basic Substance Stays BlueTurns Blue Neutral Substance Stays BlueStays Red

16. Examples You dip a red litmus paper in a liquid and it stays red. What is your liquid (acid, base, neutral) What would you do next? What would you see?

17. pH Scale

19. How Does It Work Is a lemon (pH 2) only slightly more acidic than battery acid (pH 0.2)? Does this makes? Every increment is increase by a factor of 10!!

20. Universal Indicator

21. Battery Acid0.2 Stomach Acid1.2 Lemon Juice2.0 Vinegar2.2 Apple3.0 Tomato4.2 Rain5.6 Milk6.6 Pure Water7 Human Blood7.4 Baking Soda8.2 Milk of Magnesia10.5 Oven Cleaner13.9

22. Homework Memory Check Questions: Page 193 Questions #8-12 Memory Check Questions: Page 193 Questions #8-12