2.  An acid is a substance that produces a hydronium ion (H 3 O + ) when placed in water.  Examples of Acids:

3.  Sour Taste  Can damage skin and eyes  Corrosive – react with metals  Conduct electricity

4.  A base is a substance that produces hydroxide ions (OH-) when dissolved in water.  Examples:

5.  Bitter Taste  Can damage skin and eyes  Slippery when mixed with water  Conduct electricity

6.  A salt forms when the negative ions from an acid combine with the positive ions from a base.  Neutralization – when the acid and base cancel each other out

7.  The pH scale is used to indicate how acidic or basic a solution is.  A change in one pH unit represents a tenfold change. For example a pH of 1 is ten times stronger than a pH of 2.

9.  An indicator is a compound that changes color at different pH values when it reacts with acidic or basic solutions.  pH testing strips  pH meters