The Effect of Osmosis on Potatoes: Benedict's Test of Dialysis
The Effect of Osmosis on Potatoes/ Diffusion of Molecules through Benedicts Test of Dialysis dubing
Introduction The focus of the lab on September 16, 2013 was Diffusion and Osmosis. Osmosis is a process in which the molecules of a solvent diffuse from an area of high concentration to an area of lower concentration, through a semipermeable membrane. Small solute molecules and water molecules can move freely through a selectively permeable membrane, but large molecules may pass through more slowly, or not at all.
During this experiment we measured the diffusion of small molecules through dialysis tubing. We used the I2K1 because it is small enough to diffuse and the starch is too large to diffuse out. By detecting the presence of particular molecules on each side of the dialysis tubing, we determined which molecules passed through the tubing and which did not. When the starch molecules react with iodine to form a dark blue compound. We used the I2K1 to test for starch and the Benedicts test to test for reducing sugar. Based on the information my hypothesis for this experiment is that the water and the iodine would diffuse through, because of their size and polarity.
Also in the lab on September 16, 2013 we discussed the effect of Osmosis on potatoes. Osmosis is a process in which the molecules of a solvent diffuse from an area of high concentration to an area of lower concentration, through a semipermeable membrane. We put the potatoes in different solutions with a different amount of sucrose in each solution, starting from 0.0 to 0.6. My hypothesis was that in from the 0.0 to 0.3 the weight of the potatoes will shrink and from 0.4 to 0.6 the potatoes will grow. If the potatoes absorb the sucrose and gain weight then they are hypotonic. But if the potatoes shrink then they are hypertonic. If they don’t change in size at all they are isotonic.
Methods
In Experiment 1, I measured the end of the dialysis bag with a ruler to 3 cm and folded. I pleated
Introduction The focus of the lab on September 16, 2013 was Diffusion and Osmosis. Osmosis is a process in which the molecules of a solvent diffuse from an area of high concentration to an area of lower concentration, through a semipermeable membrane. Small solute molecules and water molecules can move freely through a selectively permeable membrane, but large molecules may pass through more slowly, or not at all.
During this experiment we measured the diffusion of small molecules through dialysis tubing. We used the I2K1 because it is small enough to diffuse and the starch is too large to diffuse out. By detecting the presence of particular molecules on each side of the dialysis tubing, we determined which molecules passed through the tubing and which did not. When the starch molecules react with iodine to form a dark blue compound. We used the I2K1 to test for starch and the Benedicts test to test for reducing sugar. Based on the information my hypothesis for this experiment is that the water and the iodine would diffuse through, because of their size and polarity.
Also in the lab on September 16, 2013 we discussed the effect of Osmosis on potatoes. Osmosis is a process in which the molecules of a solvent diffuse from an area of high concentration to an area of lower concentration, through a semipermeable membrane. We put the potatoes in different solutions with a different amount of sucrose in each solution, starting from 0.0 to 0.6. My hypothesis was that in from the 0.0 to 0.3 the weight of the potatoes will shrink and from 0.4 to 0.6 the potatoes will grow. If the potatoes absorb the sucrose and gain weight then they are hypotonic. But if the potatoes shrink then they are hypertonic. If they don’t change in size at all they are isotonic.
Methods
In Experiment 1, I measured the end of the dialysis bag with a ruler to 3 cm and folded. I pleated