Osmosis Lab

In our 6th hour class we did a diffusion and osmosis lab. In this lab we had a solution of glucose and starch and placed it inside a bag of dialysis tubing. In a cup with iodine and water, but first tied off the ends tight to make sure they woulnt mix. After a half hour passed we checked the glucose level of the water in the cup and it came out negative. Over the weekend we let the membrane tube sit in the cup, and the results were that the fluid inside the membrane tube leaked into the cup with iodine and water. The iodine from outside the dialysis tubing also leaked in, because it  turned a different color from mixing with the starch. When we tested both the liquid in the cup and membrane tube, they both had a high level of glucose, that was definitely positive.

The group I was in and I decided to do another version of the lab and weigh the substances so we could see what left and went into the dialysis tubing. We did four different cups with the substances and water mixed in the dialysis tubing. The four different substances were corn syrup, sodium acetate, antacid tablets, and sodium bicarbonate. We weighed them three different times to make sure the results would come out accurate. The first time we weighed them, we weighed before we put them in the cup of water and cup one with antacid tablets weighed 13.43g, and the 4th cup with sodium bicarbonate weighed 11.66g. An hour later we weighed them again, and the 1st cup weighed 14.74g, the 2nd cup weighed 23.09g, the 3rd cup weighed 15.88g , and the 4th cup weighed 12.09g. We also did the same thing the day later. Cup 1 was 14.23g, the second cup was 16.23g, the third cup was 8.47g, and the fourth was 11.46g. As you cna see when we weighed them the hour later, they were at their highest, because thats the time when the water goes through all the little pores in the ddialysis tubing, and water moves very quickly because it dosent have very big molecules, so that is what made that possible. Over night and part of the next day is when the other substances started coming out slowly because they have bigger molecules than the water and are more dense, so it takes longer for them to go through the tubing. The sodium acetate collected the most water out of all of them, because the molecules of the acetate went through the pores in the membrane easier than all of the substances. Now that we did the lab again in a different way we really saw the diffusion and Osmosis come out in the experiments.

here is a Graph of the data we found out in our lab: