Lab report-2 - Lab report-2 PDF

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Lab report-2...

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OSMOSIS AND DIFFUSION LAB 1. ABSTRACT My lab report includes the introduction which includes my hypothesis and what the experiment is about, then is the materials that were used in the lab and how to use them. Then is the results wich show the experiments outcome. And finally is the conclusion which declares my hypothesis to be incorrect or correct and explains the results. 2. INTRODUCTION This is an osmosis and diffusion lab so we are trying to understand how they work. Diffusion is when molecules or atoms move from an area of high concentration to an area of low concentration. Osmosis is the diffusion of water across a membrane. The goal of this lab is to measure how much water moves into the dialysis bag when a certain amount of sucrose is present. My hypothesis is that bag will become heavier with more sucrose present. So the more sucrose allows the bag to absorbent more water making it heavier. 3. MATERIALS AND METHODS The materials include five, 8-inch pieces of dialysis tubing,volumetric flasks, beakers, a pipette,sucrose, water, a weight boat, a graduated cylinder, and a scale. Before you can start the experiment though you need to calculate how much sucrose we need fore each molarity. Then after you find the grams of sucrose was found for each molarity, the solutions were made. All solutions had 20 ml of water , this is the constant variable in each bag. The sucrose was the variable that was changed.We put the the solutions into the dialysis bags with the pipettes. Each bag was tied, then out on the scale before you put them in the water. Then you put them in water to soake for 15 minutes, then taken out again and weighed. 4. RESULTS The table represents the initial and final weights of the dialysis tubes. I also recorded the change in weight and percentage .

concentration

Initial weight (g)

Final weight (g)

Change in weight (g)

% change in wieght

0.0M

20.08

20.11

.03

.15%

0.2M

20.43

20.69

.26

1.26%

0.6M

22.56

24.12

1.56

6.47%

0.8

24.82

26.62

1.7

6.76%

1.0M

23.36

25.52

2.16

8.46%

DISCUSSION As you can see from the data collected the amount of sucrose in each bag affected the weight. As the amount of sucrose increased so did the weight. So my hypothesis ended up being supported by the data. An example of osmosis is if you put a raisin in water and the raisin gets bigger because the water soaks into the raisin. An example of diffusion is a tea bag, when you put it in youe cup of water the tea bags contents diffuse from to its higher concentration to the lower concentration of the water in the mug. An error that could have been made during this experiment could include not tying the bag more and water seeping out because of it, or even not getting all of the sucrose into the bag. 5. REFERENCES Sherry Krayesky, William Schmidt and Heather Birdsong.” Guide to Skills and Exploration in Biology Laboratory” McGraw-Hill Education, “ G;encoa Biology”...