Title: Is Chlorophyll Necessary for Starch Formation?
Aim: To test whether chlorophyll is necessary for starch formation
Hypothesis: Chlorophyll is necessary for starch formation
Materials:
Leaf x2
Gauze mat
Forceps/ tweexers
Iodine solution – 5 drops x2
Variegated leaf x2
Bunsen burner
Test tube x2
Safety goggles/ glasses
Beaker – 250 mL x2
Methylated spirits/ alcohol – 10 mL
Test tube rack
Safety gloves
Tripod
Matches
Petri dish x2
Water
Test tube peg
Measuring cylinder
Risk Assessment:
Hazard
Precaution
Bunsen burner
Keep away from flammable objects
Turn off when not in use
Use safety goggles/ glasses
Glass equipment
Keep away from edge of bench
Handle with care
Wear safety gloves
Alcohol
Keep away from Bunsen burner
Clean up spills
Wear safety gloves
Keep away from eyes
Wear safety goggles/ glasses
Iodine solution
Keep away from eyes
Wear safety goggles/ glasses
Clean up spills
Wear safety gloves
Variables:
Independent Variables (What is being changed)
Dependent Variables (What is being measured)
Controlled Variables (What is kept the same)
Control Variable
Areas that contain chlorophyll
How the leaf looks before and after the experiment
Amount of water used
Size of the beaker
Amount of iodine solution
Amount of ethanol used
Parts of the leaf that don’t contain chlorophyll
Method:
1. Place all equipment on bench
2. Set up the Bunsen burner, tripod and gauze mat and leave the Bunsen burner off
3. Pour 150 mL of water into the beaker
4. Place the beaker on the gauze mat
5. Place 2 leaves (one variegated and one normal) into the beaker
6. Turn on the gas
7. Use the matches to light up the Bunsen burner, keeping it on until the water in the beaker boils
8. Pour 10 mL of methylated spirits/ ethanol into two test tubes
9. Turn the Bunsen burner off once the water boils
10. Use forceps/ tweezers to remove the leaves
11. Place one leaf in each test tube
12. Place the test tube into the...