1. The pH Scale The measure of the difference between acids, bases and salts

2. Why do we need to know about pH? The pH of a substance is a chemical property of that substance. pH classifies a substance as an acid, base, or neutral substance Many life forms can only tolerate a small range of pH to live and function properly. Examples: Fish tanks, ponds, garden soil

3. pH pH is a measure of the amount of H + ions in a solution The pH scale runs from 0 to 14. A pH of 7 is NEUTRAL, less than 7 is acidic, more than 7 is basic

5. Acids Sour taste React/Corrode metals CHANGES blue litmus paper to red Neutralizes bases Releases H+ ions in water (acids start with H!) Found in: foods, stomach, batteries, fertilizers Examples: HCl (hydrochloric acid) H 2 SO 4 (sulfuric acid) HNO 3 (nitric acid)

6. Bases Taste bitter Feels slippery Can irritate your skin CHANGES red litmus paper blue –(remember Bases and Blue) Neutralizes acids Releases OH- ions in water (most end with OH) Found in: Cleaning agents and antacids Examples: NaOH (sodium hydroxide) LiOH (lithium hydroxide) KOH (potassium hydroxide)

7. When Acids and Bases Mix When acids and bases combine, they NEUTRALIZE!! When strong acids and strong bases are reacted with one another, a salt and water are the only products (totally neutral!) Examples of Neutralization Reactions: –HCl + NaOH  NaCl + H 2 O –HCl + LiOH  LiCl + H 2 O –HCl + KOH  KCl + H 2 O

8. Salts Formed when an acid and a base are reacted with one another (NEUTRALIZATION!) Made of a metal and a nonmetal AKA – an ionic compound! NaCl, KCl, MgCl 2