September 28th /09 LAB PRACTICE No. 2 TITLE: Properties of the elements Life substances

PURPOSES 1.Recognize some properties of the elements. 2.Recognize some life subtances.

HYPOTHESIS Make your own hypothesis

MATERIALS PART 1  Lab apron (Individual)  Cover mouths (Individual)  Iron slides  Aluminium slides  Carbon  Cupper slides  Magnesium  Sulphur  Bunsen burner  Combustion spoon  Ligther or Matches (In group)  Stopwatch (In group)

MATERIALS PART 2  Milk (Group)  Water  Coconut milk (Group)  Onion juice (Group)  Potato juice (Group)  Starch solution  Orange juice (Group)  14 test tubes  Test tubes racks  Hot plate  Benedict’s Reagent  Lugol’s Reagent  Beaker

PROCEDURE PART 1  Place the elements provided by you teacher on the lab table.  Observe them and describe their: colors, textures, smells and shapes.  Use the bunsen burner carefully, to test each of the elements heat conduction capacity, by controlling the time in seconds they use to get warm.  Use the combustion spoon to place on it each subtance and heat again with the bunsen burner until five minutes and observe if some of them melt or not.  Design a table to record your results.

PROCEDURE PART 2  Number each test tube from 1 to 7 making two copies A and B. (1A, 2A…. 1B, 2B….)  Place the tubes in the test tubes racks.  In each test tube add the substances as follow: 1.Tubes 1A and B: Water 2.Tubes 2A and B : Orange juice 3.Tubes 3A and B : Milk 4.Tubes 4A and B : Coconut Milk 5.Tubes 5A and B : Potato juice 6.Tubes 6A and B : Onion juice 7.Tubes 7A and B : Starch solution

PROCEDURE PART 2  Add to the test tubes sample A Benedict’s solution 5 drops. Make observations.  Heat the test tubes A, in the beaker with water until boiling point.  Make your observations  Add to the test tubes sample B Lugol’s solution 5 drops. Make your observations.  Design your own table to record the results.