To study the size of molecules that can diffuse through a semi permeable membrane. 2. Problem Statement: What size molecules can diffuse through a semi permeable embrangling tubing? 3. Hypothesis: The smaller the molecules, the easier to pass through a semi-permeable membrane. //Water/glucose molecules can diffuse through the Viking tubing but not the starch/sucrose molecules 4.
Variables: Manipulated: Size of molecules ‘Type of substances Responding: Diffusion of molecules through semi permeable membrane/ Viking being/ Change in water level in capillary tube (seismometer) Fixed: Volume of solution in the Viking tubing/ Temperature/ Time 5. Apparatus: Beaker, test tube, Bunsen burner, measuring cylinder, syringe, stopwatch. Materials Benedicts solution, iodine solution, Viking tubing, starch suspension, glucose solution, thread 6.
Technique: Carrying out food test on glucose/starch // Using Benedicts solution/ladino solution on the liquid outside the Viking tubing in the beaker and record the result]/ Measure and record the change in level of liquid in capillary tube using a ruler. 7. Procedure: 1. A Viking tubing is soaked in water to soften it. 2. The Viking tubing is tied at one end of the tube tightly with a piece of thread. 3. Viking tubing is filled with 10 ml glucose and 10 ml starch solution using a syringe. 4. The other end of the tube is tied tightly with a piece of thread.