1. Chapter 9 Acids and Bases

2. Vocabulary
Acid—a hydrogen containing compound that ionizes in water to produce hydrogen ions and is a proton donor
Base—a hydroxide containing compound that ionizes in water to produce hydroxide ions and is a proton acceptor.
Indicator—compounds that show a definite color change when mixed with an acid or base.

3. Emulsify—dissolves fats and oils
Electrolytes—a substance whose water solution conducts an electric current.
Emulsify—dissolves fats and oils
Salt—compound formed from the positive ion of a base and the negative ion of an acid. The compound is neutral.
Neutralization—the name of a reaction between an acid and a base.
Insoluble—will not dissolve in water.

4. Acids and Bases Around Us
Acids and bases are all around us every day.
Acids are in aspirin, vitamin C, oranges, grapes, lemons, grapefruit, apples, milk, tea, pickles, vinegar, and carbonated beverages
Bases are in lye, milk of magnesia, deodorant, ammonia, and soaps.
Acid is necessary for digestion and bases, such as antacids help when our stomach hurts.
Industry depends on acids and bases as well. Metals are cleaned with acids. Bases are used for making fertilizer and synthetic fibers. Both are used to make medicine.

5. Turn to your partner and name two common things in which you find acids and two common things in which you find bases.

6. Properties of Acids Acids taste sour.
Acids affect the color of indicators Litmus paper changes from blue to red.
Acids react with metals for form H2 and a metal compound. The acid corrodes the metal and produces a residue.
All acids contain hydrogen, but not everything that contains hydrogen is an acid. When an acid is mixed with water, acids ionize to produce hydrogen ions (H+). This ion is rapidly surrounded by water to form a hydronium ion H3O.

7. Common Acids Strong Acids Weak Acids Sulfuric Acid—H2SO4
Nitric Acid—HNO3
Hydrochloric Acid—HCl
Strong acids are good electrolytes.
Weak Acids
Acetic Acid—HC2H3O2
Carbonic Acid H2CO3
Boric Acid—H3BO3
Weak acids are poor electrolytes.

8. Properties of Bases Bases taste bitter.
Bases are slippery to the touch.
Bases turn litmus paper from red to blue.
Bases emulsify
All bases contain the hydroxide ion (OH-).
When dissolved in water, bases produce this ion. Because the hydroxide ion can combine with the hydrogen ion and form water, bases are referred to as proton acceptors.

9. Common Bases Strong Bases Weak Bases
Strong bases are good electrolytes.
Potassium hydroxide—KOH
Sodium hydroxide—NaOH
Calcium hydroxide—Ca(OH)2
Weak Bases
Weak bases are poor electrolytes.
Ammonium hydroxide—NH4OH
Aluminum hydroxide—Al(OH)3

10. Turn to your partner and list two characteristics of an acid and a base. Then try to name one acid and one base.

11. Acids and Bases in Solution: Salts
To measure the acidity of a solution, the pH scale is used. This measures the concentration of H3O (hydronium).
pH is a scale from 0 – 14. Seven is neutral; 0 – 6 is acidic; 8 – 14 is basic.
Strong acids have low pH values. Strong bases have high pH values.

12. Determining pH pH is determined by using an indicator. Litmus
Phenolphthalein
pH paper
Methyl orange
Bromthymol blue
Red cabbage juice
Grape juice

13. Incidator Acid Base Litmus paper Red Blue Colorless Pink Red to pink
Phenolphthalein
Colorless
Pink
pH paper
Red to pink
Blue to green
Methyl orange
Yellow
Bromthymol blue
Red cabbage
Grape juice

14. Formation of Salts
When acids react chemically with bases they form salts. The process is called neutralization.
The reaction produces a salt and water.
Many of the salts formed are insoluble.
The insoluble substance that crystallizes is called a precipitate because they fall out of the solution.
Example:
HCl + NaOH  H2O + NaCl

15. Exercise your brain!!!
Write the chemical equation to demonstrate the neutralization of sulfuric acid and sodium hydroxide.
Here is a hint:
Sulfuric acid is H2SO4
Sodium hydroxide is NaOH
When you think you have it, come write it on the board 