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To investigate the effect of placing pieces of potatoe in a given strength of sucrose solution.Prediction:I predict that, as the solution becomes more concentrated the more the potatoe cells will shrink, as the water

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Introduction

Osmosis Osmosis What is osmosis? If two solutions of different concentration are separated by a semi-permeable membrane which is permeable to the smaller solvent molecules but not to the larger solute molecules, then the solvent will tend to diffuse across the membrane from the less concentrated to the more concentrated solution. This process is called osmosis. Osmosis is of great importance in biological processes where the solvent is water. The transport of water and other molecules across biological membranes is essential to many processes in living organisms. The energy which drives the process is usually discussed in terms of osmotic pressure. I have devised an experiment using osmosis; Aim: To investigate the effect of placing pieces of potatoe in a given strength of sucrose solution. Prediction: I predict that, as the solution becomes more concentrated the more the potatoe cells will shrink, as the water, of higher concentration inside the potatoe cells, flows down a concentration gradient into the solution, which has a lower concentration of water molecules. ...read more.

Middle

I will cut out ten pieces potatoe with a knife. 2. I will label five of the potatoes "1" and the other 5 "2" 3. Using the scales I will weigh the potatoe to 2.d.p. and record the weight. 4. I will fill four measuring cylinders with exactly 40ml of sucrose solution. Each of the four cylinders will have a different strength solution. The solutions I will be using are .2M, .4M, .6M, and .8M. I will fill a fifth cylinder with 40ml of water as a control. 5. At this point I will prepare my stopwatch. 6. The potatoe pieces can now be placed into the Petri dishes and I will then add the solutions of sucrose and the control of water. 7. As the potatoe piece is placed in the Petri dish, the timer should be started. After 30 minutes the potatoe pieces will be removed from the Petri dishes. 8. ...read more.

Conclusion

0.435 Percentage change in mass (%): 1) 4.905 2) 0.441 3) -2.021 4) -4.77 5) 10.308 Conclusion In conclusion to my investigation, when I use 0.4 M level sucrose, the mass reaches an isotonic level - the water and sucrose solution level is equal. When I use 0.2 M strength of sucrose solution, the mass becomes hypertonic - there is more sucrose solution than water. And finally when I use 0.6 M and 0.8 M strength of sucrose solution, the mass become hypotonic. My prediction was correct, as the strength of the sucrose increases, the more the potatoe cells shrink. This is due to the reasons the water, of higher concentration inside the potatoe cells, flows down a concentration gradient into the solution, which has a lower concentration of water molecules. If I were to do this experiment again, I wouldn't change anything due to the fact that the experiment was successful and my method worked. Explain my graph More conclusion Evaluation - critisize n change ?? ?? ?? ?? 2 ...read more.

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