Diffusion Of Osmosis Lab Report

In the first part of the lab we were able to study the diffusion of various carbohydrates and the osmosis of water. Diffusion is the process of small molecules moving through a semipermeable membrane while osmosis of water is the movement of water through a semipermeable membrane from an area of high water potential (low solute potential) to an area of low water potential (high solute potential). Both diffusion and osmosis move in the direction that would create equilibrium on both sides of the semipermeable membrane. Equilibrium is reached when there is an equal concentration of solute and solvent on both sides of the semipermeable membrane. A semipermeable membrane is a selective membrane that only allows good materials into the cell and …show more content…
As the iodine molecules left the water, the solution started lightening up because it was getting closer to being pure water and the starch molecules were too large to diffuse out of the dialysis bag to alter the water and iodine solution outside of the bag. The glucose however, did manage to diffuse out of the bag and because it was clear, it had no impact on the colour of the iodine and water solution. When we weighed the dialysis bag we found that it had gained weight, this was due to the fact that the iodine molecules were diffusing into the bag and nothing was diffusing out. We then tested for the presence of monosaccharides and some disaccharides using the Benedict 's Test. What we found was that the dialysis bag and the beaker all contained sugar while the control (water) did not. It makes sense that the dialysis bag would test positive for the presence of sugars because we had put glucose and starch into the bag. Glucose is a monosaccharide which is what the Benedict’s Test was looking for. It also made sense that the beaker tested positive because some of the glucose managed to diffuse out of the dialysis bag and into the iodine solution in the