• Join over 1.2 million students every month
  • Accelerate your learning by 29%
  • Unlimited access from just £6.99 per month

In my experiment I plan to find out whether the concentration of sugar in water affects how much water will go into a potato chip. I will find this out by osmosis

Extracts from this document...


Biology Coursework Introduction: In my experiment I plan to find out whether the concentration of sugar in water affects how much water will go into a potato chip. I will find this out by osmosis. Osmosis is the movement of water molecules across a partially permeable membrane from an area of high water concentration to an area of low water concentration. I have chosen potato chips for my experiment, due to it having similar cells to a plant. It has a partially permeable membrane and the cell wall within the potato controls the water intake. Hypothesis: For the investigation, I think that the lower the concentration of sugar in the test tube, the larger the mass of the potato chip will be. And the higher the concentration, the smaller the mass of the potato chip will be. I think this, because I know that osmosis is the movement of water molecules from an area of high water concentration (in the water itself), to a low concentration (in the potato chip). Therefore, the chips in higher water concentrations will have a larger mass, than in higher sugar solutions. I predict that if the potato is in 0.6 or 0.8 molar solution, then the increase in mass due to osmosis will be little, as there is more sugar that water in the solution. And the net movement will therefore be outwards. If it is in 0.4 molar solution, the mass should increase a little, although there would be a small option for a net change, due to the concentration being the same in and outside of the potato chip. ...read more.


1.30 1.24 1.31 1.28 -0.47 0.8 1.75 1.64 1.55 1.65 1.14 1.01 0.95 1.03 -0.62 Concentration of sucrose Percentage change Average percentage change 1 2 3 0 26.25 23.39 22.85 +24.16 0.2 4.58 5.19 3.55 +4.44 0.4 -6.74 -8.72 -8.39 -7.95 0.6 -26.55 -27.90 -25.14 -26.53 0.8 -34.86 -38.41 -38.71 -37.53 (Graph attached) Analysis: Looking at the graph you will notice that the graph shows a positive correlation. My results agree with my prediction in the sense that they are showing the same thing that I had predicted. Which was, that the potato chip would increase in mass when it was put into pure water and would decrease in mass when put into pure sucrose solution. The steepness of the graph refers to how quickly the potato lost and gained weight. From 0-0.2, there is hardly a curve showing that it lost weight quickly, although the rest of the graph shows more of a curve, showing us that the weight decreased a lot faster as the concentration of the sucrose became higher. The line on the graph crosses the x axis at 0.24, showing us that at this point of concentration; the concentration of solution is the same inside the potato chip as well as out. Splitting the graph in two from where the line hits the x axis, the mass gain differs. Before it hits the line, the mass gain decreases, whereas after it hits the line, the mass gain increases. ...read more.


1, 1/2, 1/4, 1/8, 1/16, 1/32) this would show better the relationship between sugar solution concentration and the amount of osmosis occurring. We weighed the potatoes accurately, resetting the scales to zero every time we had finished, and taking done results with 2 d.p. Measuring the amount of solution being put into the syringes, we used a measuring cylinder. If I were to do this experiment again I would consider using a syringe to measure the volume, to receive a more accurate measurement. The results shown in the table are varied i.e. not having recurring numbers or amounts more than 2g apart. The results are reliable due to this, as we have don't have any results that vary incredibly, but are close together. With this our mean can be more reliable. The points plotted on the graph are the percentage change, showing the difference from the initial and final mass. The formula for this is shown earlier on. If able to hypothesise what would happen in this experiment again, I wouldn't change anything, due to the obvious trend shown on the graph, supporting my hypothesis. Although, there is always the possibility to find out the affects of osmosis in related situations, not using a potato. We could do this with a variety of plant cells, due to their expandable cell wall, for example, celery. By putting food dye into the water they feed off of, we can see how it affects the leaves. Using Carnations as an example is also a god way of showing the affects of osmosis. ?? ?? ?? ?? Nadine Rowe 10e ...read more.

The above preview is unformatted text

This student written piece of work is one of many that can be found in our GCSE Life Processes & Cells section.

Found what you're looking for?

  • Start learning 29% faster today
  • 150,000+ documents available
  • Just £6.99 a month

Not the one? Search for your essay title...
  • Join over 1.2 million students every month
  • Accelerate your learning by 29%
  • Unlimited access from just £6.99 per month

See related essaysSee related essays

Related GCSE Life Processes & Cells essays

  1. 'Investigating how isotonic, hypertonic and hypotonic solutions affects the total mass of a potato ...

    I should have used a larger range in order to get more accurate results and draw a firm conclusion. So in the real experiment instead of using three different concentrations I will use seven different concentrations. This is a suitable, wider range of concentration and is more appropriate.

  2. Osmosis is defined as 'the movement of water molecules from an area of high ...

    Prepare the potato samples, cut out tubes using the same cork borer and then cut them to 2cm long using a scalpel. Making sure you clean your equipment to prevent contamination. 3. Immediately weigh each sample, and then place in the bathing solution. 4. Leave for 24 hours. 5.

  1. Discover what effect water with different NaCl concentrations have on potatoes, and find out ...

    20ml of each molarity is required. 9. Syringe - To make sure that the same molarity of water goes into each beaker to make it a fair test. It's more accurate than measuring cylinder. I have chosen 20ml for each beaker.

  2. Osmosis coursework. The aim of this investigation is to find the best concentration ...

    because the solution will not make the chips absorb water nor loose much water because the solution would be isotonic which makes this the perfect concentration to store the chips in. Preliminary Investigation The reason I am doing a preliminary report is because if we do anything incorrect we will

  1. An Experiment to Find Out How the Concentration affects osmosis

    I will measure how the weight of the pieces of potato are affected by recording the change in the mass of the pieces. Fair Test To make it a fair test I will measure the change in mass, for seven different concentrations of salt solution.

  2. Looking at how concentration affects the movement of water particles through a partially permeable ...

    Water will diffuse from a region of higher to a region of lower potential. Water potential values (?) Higher Lower Direction Zero 0 of water Less negative - 500Pa diffusion More negative -1000 Pa The water is in fact diffusing from: the weaker solution (high solution)

  1. The aim of this experiment is to find out what effect altering the concentration ...

    The results table is maybe not as accurate as it could have been, but it was decided that solutions to the strength of 0.5M would be used, as after this point the results of the average change in length were the same.

  2. An Investigation to determine the Water potential of Potato cells.

    Please, do not circulate this writing elsewhere on the internet. Anybody found doing so will be permanently banned. Pilot studycogf gfr segfgfw orgf gfk ingf fogf gf. A pilot experiment was conducted in which three different shaped potato tissue pieces were placed into different sucrose solutions for 20 minutes.

  • Over 160,000 pieces
    of student written work
  • Annotated by
    experienced teachers
  • Ideas and feedback to
    improve your own work