1. Acids and Bases

2. Properties of Acids þ Produce H + (hydrogen) ions in water þ Taste sour þ Corrode metals þ React with bases to form a salt and water þ pH is less than 7 þ Turns blue litmus paper to red “Blue to Red A-CID”

3. Why the symbol for soda? Acetic acid (vinegar) Ascorbic acid (lemon juice) Hydrochloric acid (stomach acid) Examples of Common Acids

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

5. Properties of Bases Many household products contain bases Strong bases can be dangerous

6. Properties of Bases Bases can help to ease the effects of too much stomach acid They are conveniently called ANTACIDS

7. Examples of Common Bases  Bleach  Laundry detergent  Shampoo  Soaps, toothpaste  Tums, Alka-Seltzer (antacids)

8. Water - an acid or base? Water is neither acidic or basic – it is the only substance that is naturally neutral. pH = 7 (neutral)

9. Litmus Paper A base will turn litmus blue An acid will turn litmus red

10. Acid-Base Reactions A reaction between an acid and a base is called a neutralization

11. The pH scale is a way of expressing the strength of acids and bases. pH 1-6 = acid pH 7 = neutral pH 8-14 = base

12. pH Scale A pH lower than 7 is acidic A pH higher than 7 is basic (alkaline) If the pH is 7, the solution is neutral

13. pH indicators Indicators are dyes that can be added that will change color in the presence of an acid or base.