Diffusion And Osmosis Lab Report

Jully Garcia

Diffusion and Osmosis

Lab Report

Introduction

We did this experiment to find out the percent of starch concentrations in two different types of solutions. Osmosis is diffusion that involves the transport of water. In osmosis, water moves selectively from high concentration to low concentration.The whole point of the membrane is to allow certain molecules and the ones left behind don't get allowed in. To get to understand more diffusion is the movement of molecules from an area of high concentration to an area of low concentration. Osmosis is the diffusion of water and the main difference between osmosis and diffusion is that osmosis involves water and diffusion can be in the air.

Hypothesis

The glucose will diffuse out of the

We got a 30 cm piece of dialysis tubing and soaked it in distilled water for a few minutes, then closed the end of the tube with a rubber band creating a bag so in the end of the tube no solution will leak.We then added 15 ml of glucose in the bag then 15 ml of starch solution. We then held the bagan mixed it and recorded the colors. Then we performed benedict's test and had 4 different test tubes that was the control tube, bag tube, and beaker tube and added 1 drop of benedict's reagent. After that we heated the test tubes in a water bath for about 3

The Benedict’s test is to find if there is any glucose and then in our test it indeed indicated that their was glucose by turning red.This supports our hypothesis because it allowed glucose in from the starch and glucose solution. Since there was no change in the second Benedict’s test it shows that it did not let any iodine into the solution.

2) The first test it allowed glucose in due to the fact when we observed its color it was redt. For the dialysis bag the original contents of the bag is starch and glucose, and placed in an I2KI solution. The glucose and I2KI is able to diffuse outside the dialysis bag while the starch is stuck in the bag. This mixture of I2KI and glucose results in the purple color. For the beaker the water and iodine, and placed into it is the dialysis bag of starch and glucose. The mixture of iodine and glucose, keeps the color of the solution orange, since only diffusion is occurring. 3) We can now assume that glucose and iodine molecules are approximately the same size molecules while starch is larger because iodine and glucose could pass through the dialysis bag, while starch molecules could not due to the fact that the the molecules are