1. Acids and Bases Acids and Bases

2. Acids Have a sour taste. Vinegar is a solution of acetic acid. Citrus fruits contain citric acid. React with certain metals to produce hydrogen gas. React with carbonates and bicarbonates to produce carbon dioxide gas Have a bitter taste. Feel slippery. Many soaps contain bases. Bases

3. Some Properties of Acids  Produce H + (as H 3 O + ) ions in water (the hydronium ion is a hydrogen ion attached to a water molecule)  React with bases to form a salt and water  Corrode metals  Electrolytes  Taste sour  pH is less than 7  Turns blue litmus paper to red  “Blue to Red A-CID”

4. Some Properties of Bases  Produce OH - (hydroxyl) ions in water  Taste bitter, chalky  Are electrolytes  Feel soapy, slippery  React with acids to form salts and water  pH greater than 7  Turns red litmus paper to blue “Basic Blue” “Basic Blue”

5. The pH scale is a way of expressing the strength of acids and bases. pH can be viewed as an abbreviation for power of Hydrogen - or more completely, power of the concentration of the Hydrogen ion. 0 - 7 = acid 7 = neutral 7 – 14 = base

6. pH of Common Substances pH paper will indicate the pH of a substance by the color it changes in a solution

7. LecturePLUS Timberlake7 Learning Check AB1 Describe the solution in each of the following as: 1) acid 2) base or 3)neutral. A. ___soda B. ___soap C. ___coffee D. ___ wine E. ___ water F. ___ grapefruit

8. LecturePLUS Timberlake8 Solution AB1 Describe each solution as: 1) acid 2) base or 3) neutral. A. _1_ soda B. _2_ soap C. _1_ coffee D. _1_ wine E. _3_ water F. _1_ grapefruit

9. LecturePLUS Timberlake9 Learning Check AB2 Identify each as characteristic of an A) acid or B) base ____ 1. Sour taste ____ 2. Produces OH - in aqueous solutions ____ 3. Chalky taste ____ 4. Is an electrolyte ____ 5. Produces H + in aqueous solutions

10. LecturePLUS Timberlake10 Solution AB2 Identify each as a characteristic of an A) acid or B) base _A_ 1. Sour taste _B_ 2. Produces OH - in aqueous solutions _B_ 3. Chalky taste A, B 4. Is an electrolyte _A_ 5. Produces H + in aqueous solutions