Investigating Osmosis Using Potato Cylinders
The aim of this investigation is to see how the sugar concentration of
a solution eventually affects the size of a submerged potato
cylinder. I am conducting this experiment to further my understanding
of osmosis. The increase or decrease of the size of the potato
cylinder can be explained by osmosis.
Introduction:-
The core scientific principle, related to my investigation is that of
Osmosis, below I intend to relay information thus.
Osmosis:-
Osmosis is basically a form of diffusion, but more specifically: it
is the movement of water molecules from an area of high water
concentration, through a partially permeable membrane to an area of
lower water concentration.
Partially permeable membrane:-
A partially permeable membrane is a membrane, with holes so small that
only water molecules are small enough to fit through, bigger molecule,
for instance, sugar and salt are not small enough to fit through.
In my experiment I will be testing Osmosis with a potato in relation
to the solution that it is in, one solution will be pure water, the
second will be a 5% glucose concentration, and then the next a 10%
glucose concentration, and then a 15% glucose concentration. My
hypothesis and the experiment will predominately affected by the type
of solution that the potato cylinders are in, i.e. the solution that
the potato cylinders are in will affect the results, that is whether
the potato cylinders shrink, stay the same size, or grow larger:
Hypertonic Solutions: In a hypertonic solution the solution will have
a higher solute concentration that the potato would, when th...
... middle of paper ...
...his will further the
relativity and congruence that I hope to achieve in my results.
Because I am checking the affect of osmosis on the weight and size of
potato cylinders I will keep the potato cylinder size the same but
change the concentration of sugar in different solutions to see how it
affects the cylinders.
Results:-
Initial potato weight(g)
Average Potato Weight(g)
Concentration of Solution
Weight after osmosis(g)
Average Weight after Osmosis(g)
1
2.009
1.9825
0%
2.108
2.1165
1.956
2.125
2
1.970
1.9605
5%
1.974
1.9625
1.951
1.951
3
1.490
1.7800
10%
1.983
1.6875
2.070
1.392
4
1.890
1.9400
15%
1.690
1.745
1.990
1.800
The Effect of Solute Concentration on the Rate of Osmosis Aim: To test and observe how the concentration gradient between a potato and water & sugar solution will affect the rate of osmosis. Introduction: Osmosis is defined as, diffusion, or net movement, of free water molecules from high to low concentration through a semi-permeable membrane. When a substance, such as sugar (which we will be using in the experiment we are about to analyse), dissolves in water, it attracts free water molecules to itself, and in doing so, stops them from moving freely. The effect of this, is that the concentration of (free) water molecules in that environment goes down. There are less free water molecules, and therefore less water molecules to pass across a semi-permeable membrane, through which sugar molecules and other molecules attached to them are too big to diffuse across with ease.
Conclusion In my conclusion, the potatoes with the lowest concentration gained the most mass, and would become hard relating back to the Turgor theory I stated earlier. In contrast to this, the potatoes in the most concentrated solution lost the most weight thus becoming plasmolysed and limp also relating back to the background I have mentioned earlier. Evaluation In general the experiment was succesful the results were consistent and also were in accordance with the theories made at the start.. The experiment could have been improved by: · More subjects used instead of potatoes · More potatoes · Wider time ranger · Different molarities Using this variety of methods could have improved the experiemnt, however I was generally satisfied with the results of this osmosis experiement.
So the experiment will be based upon the movement of water. The first potato chip will be placed in a zero percent solution. I believe that this will increase the mass. I believe this because the zero percent solution has a lower concentration than the cell sap inside the potato. The potato takes on the water through osmosis and the cell pushes out from inside the cell making it swell and become more rigid.
I am going to carry out an experiment to measure the change in mass of
When doing this experiment I was able to see the effect of different concentrations on the rate of osmosis, each was done by measuring the initial mass and length of the potato cylinder and after osmosis, the results were conducted to show that as the sucrose concentration increases the rate of osmosis also increases as I said in my hypothesis thusly making a direct decrease in mass.
So what is happening is water is moving from a high concentration, i.e. a dilute solution to a more concentrated solution. Preliminary Work on Osmosis I am going to test carrots in a small osmosis experiment to see how the experiment works with carrots and salt solution and water. Variables 1) Temperature - Keep the same 2) Number of days left soaking - Keep the same 3) Size of beaker - Keep the same 4) Size of carrots - Keep the same 5) Concentration of salt solution -
Investigating the Effect of Sugar Solution on the Weight and Size of Potato Cells Aim: To investigate whether the different concentration of sugar solution will affect the weight and size of the potato cells. General background information: Osmosis is defined as the movement of water or any other solution's molecules from an area in which they are highly concentrated to a region in which they are less concentrated. This movement must take place across a partially permeable membrane such as a cell wall, which lets smaller molecules (E.g. water) through but does not allow larger solute molecules to pass through. The molecules will continue to diffuse until the area in which the molecules are found to reach a state of equilibrium, meaning that the molecules are equally distributed throughout the cell, with no area having a higher or lower concentration than any other hence equal. Hypothesis/prediction: For this particular investigation I believe that the lower the concentration of the sugar solution in the test tube the mass of the potato will be greater and the longer the potato cells will be.
Investigating The Effect Of Concentration Of Salt Solution On The Mass Of Potato Chips Aim: The aim of this investigation is to see whether the amount of salt solution affects the mass of the potato chip Hypothesis: In the solution below, water will diffuse from the dilute solution into the concentrated solution through the process of osmosis. Therefore the dilute solution level will fall and the concentrated level will rise Line Callout 2: Disapproved (is unable to go through the semi permeable membrane O Line Callout 2: Approved (is able to go through the semi permeable membrane P Salt solution Water [IMAGE] When a substance such as salt dissolves in water, the substance's molecules stick with some of the water molecules, so the concentration of the water molecules decreases. When the water molecules are the same concentration on both sides of a semi permeable membrane and salt is dissolved into one of them, osmosis will occur as shown in the diagram below.
When I am not using them I will place them away from my experiment and
Determining the Concentration of the Cell Sap in Potato Storage Tissue Aim: To determine the concentration of the cell sap in potato storage tissue. By using Osmosis, determine what the sugar concentration of cell sap is. Prediction I predict that the potato segment in the distilled water will definitely gain in weight because the solution outside it has a much higher concentration of water then in the cell sap meaning Osmosis will occur and the potato segment take in water. I predict that 0.2M sugar solution will also gain weight because it still has quite a high concentration of water outside the potato. The potato in the 0.4M solution will gain weight but the potato in the 0.6M and 0.8M solutions will lose weight.
Osmosis in Potato Tubes Osmosis: Osmosis is the movement of water molecules through a semi-permeable membrane from a high concentration to a low concentration. Diagram: [IMAGE] [IMAGE] Aim: To see the effects of different concentration of sugar solution on Osmosis in potato tubes. Key factor: In the investigation we change the sugar solution from: 0%-10%-20%-30%-40%-50% this is the independent variable; the dependant variable is the change in mass. Prediction: I predict that all the potato tubes in pure water or low concentration sugar solution will swell because water enters their cells by osmosis.
water in the potato, then the water will go out of the potato and into
The Effect of Water Concentration on the Mass of Potato Tissue Aim: The aim of this investigation is to discover the effect of water concentration on the mass of potato tissue, and also to investigate the movement of osmosis through potato tissue. Scientific Knowledge: When a substance such as a sugar dissolves in water, the sugar molecules attract some of the water molecules and stop them moving freely. This, in effect, reduces the concentration of water molecules.
When you place a potato chip in a salt or sugar solution, then if the
= == In my investigation to find out how salt solution concentration affect the mass of potatoes, I will investigate how much the mass of a potato changes if I leave it in a beaker of water with a specified salt concentration for half an hour. I will change the salt concentration after each experiment. Background Knowledge --------------------