1. Acids, Bases, and Salts Get to know them!

2. Facts about Acids and Bases An acid is a substance that produces Hydrogen Ions ( H + ). A bases is a substance that produces Hydroxide Ions (OH = ). This controls the properties of acids and bases.

3. Some Examples Acids Strong: –Hydrochloric acid –Sulfuric acid –Nitric acid Weak: –Phosphoric acid –Citric acid Bases Strong: –Potassium Hydroxide –Sodium hydroxide –Calcium hydroxide Weak: –Ammonium Hydroxide –Aluminum Hydroxide

4. Characteristics Acids: –Taste sour –Turn blue litmus paper red –pH lower than 7. Bases: –Feel slippery –Taste Bitter –Turn red litmus paper blue. –pH higher than 7

5. Strengths of Acids and Bases Depends on how easily they form ions in solution. pH is a measure of the hydronium ion concentration of a solution. Stronger acids have lower pH. Stronger bases have higher pH.

6. The pH Scale

7. Salts When an acid chemically combines with a base, the reaction is called neutralization. A salt is produced when the H 3 O + ions from an acid react with the OH - ions from a base to produce water molecules and a salt through a process called neutralization.

8. Neutralization The properties of the acid and base are lost as two neutral substances, water and a salt, are formed. Example: H + Cl = + Na + OH = H 2 O + NaCl Many salts formed during neutralization form as a precipitate and do not dissolve in the water. This process is called precipitation. Examples include: magnesium carbonate, silver chloride, and aluminum phosphate.

9. Acid Rain Acid rain is formed when substances in the air react with rainwater to make the rainwater acidic. Acid rain production is increased when oxides are released into the air by the burning of fossil fuels. Acid rain is harmful to plants and animals.