September28th /09LAB PRACTICE No. 2

TITLE: Properties of the elementsLife 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: Water2. Tubes 2A and B : Orange juice3. Tubes 3A and B : Milk4. Tubes 4A and B : Coconut Milk5. Tubes 5A and B : Potato juice6. Tubes 6A and B : Onion juice7. 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.