Finding Out the Changes of Mass in Potato Chips Due to Osmosis
Aim:
We have been asked to investigate the effect that osmosis has on
potato chips.
Prediction:
I predict that the potato cylinder in the lowest sugar solution
(water) will gain the most mass through osmosis, whereas the 80% sugar
concentration will lose the most mass through osmosis. I predict this
because I think that the potato chips will try to gain and lose water
between the two sides of its cell wall in order to reach an
equilibrium between them. Because the 80% sugar solution has a high
amount of sugar molecules, which can not diffuse through the membrane,
I think that the potato will lose water in order to make the solution
on the outside of its membrane equal to the water concentration on the
inside (thus losing mass). I also predict that the other
concentrations (60%, 40%, and 20%) will lose mass, but in lower
numbers compared to the 80% sugar solution (the lower the
concentration, the higher the mass). However, since the distilled
water carries no sugar molecules, I think that the potato chip will
gain water to create a balance between the two sides of the cell wall,
making it gain mass.
Scientific background:
Osmosis is the diffusion of water molecules through a selectively
permeable membrane from a region of high water concentration to a
region of low water concentration.
The direction and rate of osmosis depends on the difference in water
concentration between the two sides of the membrane. Water will still
move into an area of lower water concentration until the two
concentrations are equal.
Weak Solution.
Strong sugar solution
= Sugar Molecule
Water molecules can diffuse through the membrane easily.
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Sugar molecules too large to diffuse through the membrane.
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= Water Molecule
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Selectively permeable membrane
Preliminary results.
Mass (grams) Before experiment.
osmosis, it can works both ways so that it can pass into and out of
Investigate how the Concentration of Sucrose Solution affects the Mass of the Potato Chip Aim To find out how the concentration of sucrose solution affects the mass of the potato chip left in the solution for one day. Water Potential: The water potential of a solution is a measure of whether it is likely to lose or gain water molecules from another solution. A dilute solution, with its high proportion of free water molecules, is said to have higher water potential than a concentrated solution, because water will flow from the dilute to the concentrated solution (from a high potential to a low potential). Pure water has the highest possible water potential because water molecules will flow from pure water to any other aqueous solution, no matter how dilute. Prediction: Osmosis is the passage of water molecules from a weaker solution to a stronger solution, though a partially permeable membrane.
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.
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.
I am going to carry out an experiment to measure the change in mass of
The second potato chip will be placed in a fifty percent solution. I believe that the mass will not change for this potato chip because the concentration of the cell sap and the solution is nearly the same. This means the concentration will be nearly even inside and outside the cell. But this does not mean that osmosis is not taking place. Osmosis is the movement of water, the water still moves between the semi-permeable membranes.
The cell membrane in cells is semi-permeable and the vacuole contains a sugar/salt solution. So when a cell is placed in distilled water (high water concentration, lower water potential) water will move across the semi-permeable membrane into the cell (lower water concentration, higher water potential) by osmosis, making the cell swell to carry the extra water. This cell is now referred to as turgid. The opposite of this is where the cell becomes flaccid, where the cell membrane actually can break away from the cell wall. If this process were done with the potato cells I would expect them to increase in length, volume and mass due to the extra water.
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.
This is because the water molecules passed from a high concentration in the water, to a low concentration, in the piece of potato. Therefore, the potato in higher water concentrations will have a larger mass than in higher sucrose concentrations. i.e. The potato pieces are shown to have water potential. The attached graph shows the concentration of the sucrose solution plotted against the average mean change in mass.
I think that the potato that is put in the test tube with water in
The. So if there is a lot of salt dissolved into water surrounding the organism (in this case a potato chip) then water particles from. other cells are going to attempt to equal the concentration of water. in the solution with the water concentration in the cell. Therefore most of the water from the cells of the potato chipping will change in mass, depending on the concentration of solution.
For this experiment, I will cork a potato, cut it to size and dry it.
Prediction I think that when the potato is placed in distilled water the potato mass will increase. This is because water, has, if pure, a weaker concentration than the potato, and the water molecules move in through a partially permeable membrane by osmosis. If the potato is in a high concentration salt solution, the potato mass will decrease because the potato is less concentrated than the salt solution, and the water will move through the partially permeable membrane into the stronger solution. However, if the potato mass stays the same after the experiment, this means that the water/salt solution and the potato must be of equal concentration.
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.
Osmosis is the movement of water from a higher concentration to a lower concentration across a membrane. Osmosis is considered to be a passive transport because energy is not required in order for water molecules to move in and out. It is semi-permeable and the reason being so is because not all different molecules can enter. It leaves certain solutes out and allows certain ones in. the purpose of this lab is to see how the use of diffusion can allow the osmosis to travel across the membrane. To start off there was a sample bag containing sodium Sulfate (NaSO4), and a big beaker of sodium chloride (NaCl). We placed each in testing tubes containing different solutes which were starch, sulfate ion, chloride ion, and protein and saw how they reacted in terms of osmosis (hypertonic, hypotonic,