Effect of Sucrose Molarity on Potato Tuber Weight

Aim: To find the concentration of a potato cell cytoplasm compared to sucrose and salt. I mainly was looking to see how concentration of salt/sucrose affects the mass of the potato cores.

I know that osmosis will occur in the vegetables, but I am not sure of

Purpose: To determine the concentration of solute in the potato’s cytoplasm by measuring the change

The main purpose of the experiment was to test the idea that water would move from the higher concentration to the lower concentration. In order to test this theory, we placed potato slices in 7 different containers, each containing different concentrations of NaCl, to measure the weight change from osmosis. The containers ranged from 0M NaCl all the way to .6M NaCl. We measured the potato slices before and after placing the slices in the solutions and recorded the net change in weight to determine the tonicity of the potato cells. Our results showed that the potato slices put in a NaCl solution of .2M or higher lost weight and the potato slices put in a NaCl solution of .1M or lower gained weight. This shows that the osmolarity of the potato falls within the range of .1M to .2M, and it also proves the process of Osmosis by having the higher concentration move to the lower concentration. In addition to this, it can be concluded that the osmolarity of cells can be determined by observing the affects of osmosis.

How do different concentrations of sucrose solutions (0M, 0.2M, 0.4M, 0.6M, 0.8M, 1M) affect the mass of potato cores when in sucrose solution?

Though the theory following the hypothesis is correct and the experiment was carried out with as much attention as possible in a high school laboratory, the results obtained were still indicative of a few errors and did not support the predicted hypothesis. From the results obtained it can be concluded that as the concentration of sucrose increases the average percentage change in mass decreases. This is because the salt concentration inside the potato cubes of 10%, 15% and 20% concentration is less that in the salt concentration on the sucrose solution, thus the three cubes submerged in the 10% - 20% concentrated solution lost mass (hypertonic). However the cube submerged

Osmosis is defined as the tendency of water to flow through a semipermeable membrane to the side with a lower solute concentration. Water potential can be explained by solutes in a solution. The more positive a number is more likely it will lose water. Therefore should water potential be negative the cell the less likely it will lose water. In using potatoes the effects of the molarity of sucrose on the turgidity of plant cells. According to Clemson University, the average molarity of a White potato is between .24 M and .31 M when submerged in a sorbitol solution. This experiment was conducted with the purpose of explaining the relationship found between the mass in plants when put into varying concentrations of sucrose solutions. Should the potatoes be placed in a solution that contains 0.2M or .4M of sucrose solution it will be hypotonic and gain mass or if placed in .6M< it will be hypertonic and lose mass instead. Controlled Variables in this lab were: Composition of plastic cups, Brand of Russet Potatoes, Brand of Sweet Potatoes and the Temperature of the room. For independent variable that caused the results recorded it was the different Sucrose concentrations (0.0M, 0.2M, 0.4M, 0.6M, 0.8M, 1M). The dependent variable was the percentage change from the initial weighs to the final. The cup with .4 molarity was the closest to an isotonic solution and was used as the control group for the lab. Water potential is the free energy per mole of water. It is

out the potato and dry it to ensure excess water is not added to the

Van’t Hoff’s Law suggests that the osmotic potential of a cell is proportional to the concentration of solute particles in a solution. The purpose of this experiment was to determine if there are any differences between the osmolalities, the no-weight-changes of osmolalities, and the water potentials of potato cores in different solutions of different solutes. The percent weight change of the potato cores was calculated through a “change in weight” method. The potato core’s weight was measured before and after they were put into different concentrations of a solute for 1.5 hours. In our experiment, there were no significant differences from the osmotic potentials of our results and the osmotic potentials of other scientists work. Ending with chi square values of 2.17 and 2.71, and p values of 0.256 and 0.337, concluding that there is no difference in water potentials of potato cores in different solutions of different solutes at varying concentrations.

The aim of the sixteenth of November experiments was to observe how three different solutions with various sucrose concentration influenced osmosis in relation to three onion cells and the impact on the cells structure.

Effect of Sucrose Solution on Osmosis Aim: The aim of the experiment is to show how varying the concentration of sucrose solution affects osmosis by changing different molar solutions of sucrose and water and how it affects the potato. Introduction: In this investigation I will be exploring the effect of varying concentration of sucrose sugar solution on the amount of activity between the solution and the potatoes. Osmosis is the movement of water molecules across a partially permeable membrane from a high water concentration to a low water concentration.

However one beaker received 100 mL of Deionized water with a molarity of 0.0. Afterwards a cork borer was pushed through the potato and was twisted back and forth. Once the borer was filled it was removed from the potato. Pushing the potato cylinder out of the borer, this this step was repeated six more times in order to get seven undamaged potato cylinders. Using a sharp razor blade, the potato cylinders were both cut to a uniform length of about 5cm, and were removed of their potato skins. The potato pieces were also cut in half to give the cells a greater surface area in which it was easier to absorb the solution. After the cylinders were weighed on a balance and the data was recorded in Table 4. Using the razor blade each potato was cut lengthwise into two long halves. Then the potato pieces were transferred to the water beaker and the time they were submerged was recorded. This step was repeated for all potato cylinders in which the pieces were placed in solutions 0.1 to 0.6 M. The potatoes were incubated for ninety minutes. At the end of the incubation period the time was recorded. Then the potato piece was removed form the first sample. Next potato pieces were weighed the and the final weight was recorded in Table 4. This procedure was repeated until all samples had been weighed and recorded in the chronological order they were initially placed in the test solution. Afterwards the table was completed by recording the

In conclusion when the molarity level was at 0 and at .2 the potatoes had gained mass so therefore they were placed in a hypotonic environments. When the molarity level was .4 and above the potatoes loss mass so therefore they were placed in hypertonic environments. So the different in concentrations does change the mass of the potatoes because they determine the osmosis environments.

This would happen by using similar sizes and lengths of potato cylinders and applying the into different concentrations of sucrose (0,10%,30%, 50%, 70%) in foam cups then measuring the change in mass of the potato cylinders afterwards. Maintaining all variables unchanged such as pH, same size, covered solutions, and a constant temperature. The time taken for all potato cylinders will be 24 hours.

Data: Effect of Solute Concentration on Osmosis in Potato Cells (for the 6 groups of our class)