1. p. 42-43 in Prentice Hall Biology, Miller and Levine

2.  What just happened with the witches and their pink potion?

3.  Chemicals that respond to a change in H ion concentration  Change color depending on whether substance is an acid or a base  Examples:  litmus paper  phenolphthalein

4.  What is an ion?  Answer: positively or negatively charged atom

5.  A compound that forms H + ions in a solution  Example: Hydrochloric acid produced by stomach to digest food (HCl)

6.  Contains Hydrogen (H+)  Turns litmus paper red  Tastes sour  Dissolves metal

7.  A compound that forms hydroxide ions (OH-) in a solution  Example: Lye

8.  Contains Hydroxide  Turns litmus paper blue  Tastes bitter  Feels slippery

9.  The pH scale  What does pH stand for  Power of Hydrogen  Scale ranges from 0 to 14

10.  Acids have a pH below 7  Strong acids range from 1 to 3  Strong acid example: HCl

11.  Bases have a pH above 7  Strong bases range from 11 to 14  Strong base example: lye

13.  pH increases tenfold

14.  A water molecule can react to form ions

15.  Why is pure water considered “neutral”?  Pure water pH = 7  Number of positive hydrogen ions equal to negative hydroxide ions produced