1. Acids  Substances that donate hydrogen ions (H + ) to water to form H 3 O +  Called the hydronium ion  Examples of Acids  HCl hydrochloric acid used in pools  H 2 SO 4 sulfuric acid- battery acid  HC 2 H 3 O 2 acetic acid- vinegar  HC 6 H 7 O 7 citric acid- lemons, limes

2. Properties of acids  Taste Sour  Conduct electricity  strong electrolytes - will conduct a lot  weak electrolytes- will conduct only a little  React with metals to form hydrogen gas  Change indicators (BAR)  B lue litmus in A cid turns R ed  React with hydroxides to form water and a salt

3. Acids  ones in food are dilute  Concentrated acids - dangerous  They can burn skin and eyes  Strong acids ionize completely  All the H’s make hydronium  HCl + H 2 O  Cl - + H 3 O +  Makes lots of ions  Are dangerous

4. Acids  Weak acids only partially ionize  Only a few H’s attach to water  HC 2 H 3 O 2 + H 2 O C 2 H 3 O 2 - + H 3 O +  Can be dangerous if concentrated

5. Bases  Increases the amount of OH - in solution  Either has OH - in it or takes an H off of water  Examples of bases  KOH - in drain cleaner  NaOH - in drain cleaner  NH 3 - ammonia

6. Properties of bases  Taste bitter.  Feel slippery  Can be strong or weak electrolytes.  Change indicators (RBB).  R ed litmus paper in B ase turns B lue  React with acids to form water and a salt

7. Bases  KOH  K + + OH -  Strong bases ionize completely  Make lots of ions  Are dangerous  NH 3 + H 2 O NH 4 + + OH -  Weak bases only make a few ions  Are dangerous if concentrated

8. How Acidic?  More H 3 O + is more acidic  Measured with pH  Lower pH is more acidic  As H 3 O + goes down, OH - goes up  Higher pH more basic  pH of 7 is neutral Neutral 7 Acidic 0 Basic 14

9. pH  French origin “Pouivier Hydrogene” – means “power of hydrogen”  Measures hydronium ion concentration  Every 1 unit less of pH is 10 times more hydronium  A pH of 2 is 100 times more H 3 O + ions than a pH of 4  pH is number of places after the decimal point  pH of 2 is 0.01 Molar H 3 O +  pH of 4 is 0.0001 Molar H 3 O +  pH of 9 is 0.000000001 Molar H 3 O +

10. pH  Low pH is acid (pH 1,2,3,4,5,6)  Lots of H 3 O +  Little OH -  High pH is base (pH 8,9,10,11,12,13,14)  Little H 3 O +  Lots of OH -

11. Neutralization Reactions  Acids and bases react and neutralize each other  Strong acids make lots of ions  HCl + H 2 O  H 3 O + + Cl -  Strong bases make lots of ions  NaOH  Na + + OH -  and  H 3 O + + OH -  2H 2 O

12. Neutralization Reactions  Put acids and bases together  H 3 O + + Cl - + Na + + OH -  Cl - +Na + +2H 2 O  The Na + and Cl - make salt which is neutral  Water is neutral  Will be neutral if the right amounts of strong acids and bases are added

13. Neutralization Reactions  Weak bases will neutralize a strong acid, but not as well.  You need to add more of them  If you add enough, it will make the solution basic  Same works for weak acids and strong bases  As you add acid to a base the pH drops  As you add base to and acid the pH rises

14. Household Uses  Antacids- Weak bases that neutralize excess stomach acid  Shampoo- made from detergents  Need to keep pH between 5 and 8 or it will make the hair dull  Citric acid keeps fruit from browning  Acidic marinades tenderize meats  Drain cleaners are strong bases