1. And others…

2.  For thousands of years people have known that vinegar, lemon juice and many other foods taste sour.  However, it was not until a few hundred years ago that it was discovered why these things taste sour – They taste sour because they are all acids.  The term acid, in fact, comes from the Latin term acere, which means "sour"

3.  Acids have a PH of less than 7.  Acids taste sour  Acids are corrosive to metals  Acids can ‘burn' your skin  Acids change litmus paper red  Litmus paper helps to determine acids and bases  Acids become less acidic when mixed with bases.

4.  orange juice, lime juice or lemon juice (citric acid)  vinegar (acetic acid)  aspirin (salicylic acid)  yogurt (lactic acid)  Coca-Cola (phosphoric acid)  toilet bowl cleaner (sulfuric acid)  bathroom cleaner (muriatic acid)  wine (tartaric acid and/or malic acid)  vitamin C tablets (ascorbic acid)  urine (uric acid)

5.  Bases can also be called alkalis.  Bases can be thought of as the chemical opposite of acids.  A reaction between an acid and base is called neutralization  We will talk more about this tomorrow An example of base: soap

6.  Bases have a pH more than 7  Bases feel slippery  Converts fats and oils in skin to glycerin (slick feel)  In a sense, bases dissolve your skin… think of getting Clorox bleach on your skin  Bases turns litmus paper to a blue color.  Bases become less basic when mixed with acids.  Bases reacts with acids to form salt and water

7.  Mustards  Many medicines  Ie. Magnesium oxide – treats indigestion  Bleaches, soaps, toothpastes, window cleaners and other cleaning agents  Sodium Hydrogen Carbonate (bread soda).  Sodium hydroxide (NaOH) or caustic soda  Calcium hydroxide ( Ca(OH) 2 ) or limewater  Ammonium hydroxide (NH 4 OH) or ammonia water  Magnesium hydroxide ( Mg(OH) 2 ) or milk of magnesia

8.  Measure of how acidic or how basic More AcidicMore Basic HCl Stomach Acid Lemon Juice Vinegar Soda Rain NaOH Pure water Egg Whites Baking Soda Drano Mineral Lime Ammonia Tums

9.  ACIDS  1 - HCL  2 – Stomach Acid  3 – Lemon Juice  4 - Vinegar  5 - Soda  6 – Rain Water  BASES  8 – Egg Whites  9 – Baking Soda  10 - Tums  11 - Ammonia  12 – Mineral Lime  13 - Drano  14 - NaOH  Neutral:  7 – Pure Water

10. Acids and Bases… and others

11.  Acids start with “H”  Examples:  HCl  H 2 SO 4

12.  Bases end in “OH” (hydroxides)  Examples:  NaOH  Ca(OH) 2

13.  Metals are single elements found on the left side of the periodic table  Separated from non-metals by metalloids (staircase)  Examples  Al  Li  Can you name any other ones?

14.  Carbonates end with the elements “CO 3 ”  Examples  Na 2 CO 3  MgCO 3

15.  Salts are two elements bonded together from opposite sides of the periodic table or with a polyatomic ion  What is polyatomic ions?  Examples  NaCl  AlF 3  KNO 3