• Join over 1.2 million students every month
  • Accelerate your learning by 29%
  • Unlimited access from just £6.99 per month
  1. 1
  2. 2
  3. 3
  4. 4
  5. 5
  6. 6
  7. 7
  8. 8
  9. 9

Osmosis is the diffusion of a solvent from a less concentrated solution into a more concentrated solution through a semi-permeable membrane, permeable to the solvent but not to the solute.

Extracts from this document...


Christian MacNamara 11MC BIOLOGY - Science Investigation: Osmosis PLANNING: Scientific Knowledge Osmosis is the diffusion of a solvent from a less concentrated solution into a more concentrated solution through a semi-permeable membrane, permeable to the solvent but not to the solute. (The Oxford Popular English Dictionary, reprinted 2000, Oxford University Press.) Diffusion is the movement of particles from a high concentration to a low concentration until they are spread out evenly. (Biology Exercise Book 1, 14/09/01.) Diffusion consists of the movement of large and small molecules, and in the case of Osmosis, the small particles are water (H2O) and the large particles are sugar (sucrose). The processes of Osmosis and Diffusion will be occurring in this experiment when the water in the potato diffuses from the area of high concentration (the potato) to the area of low concentration (the solution). Water (H20): Water is chemically formulated from 2 parts Hydrogen (H2) and 1 part Oxygen (O) Sucrose (C12H22O11): is a sweet crystalline dextrorotatory disaccharide sugar that occurs naturally in most plants and is obtained commercially especially from sugarcane or sugar beets (Encyclopaedia Britannica online dictionary.) Sucrose is used in the solution for this experiment. Plasmolysis: is the shrinking of the cytoplasm away from the wall of a living cell due to outward osmotic flow of water (Encyclopaedia Britannica online dictionary.) The process of Plasmolysis will occur when the water diffuses from the potato to the sucrose solution due to Osmosis. ...read more.


This goes the same for all the other groups whom we will be sharing our results with. Measuring Apparatus: - A ruler was used to accurately measure the length of the potato cylinders to the nearest mm. - Accurate weighing scales (2d.p.) were used to measure the mass of the potato cylinders both before and after the experiment. OBTAINING EVIDENCE: Results Table of Results: (anomalies are shown in red) Experiment 1 Sugar conc.(%) Mass Before (g) Av. Mass Before (g) Mass After (g) Av. Mass After (g) % Change in Mass 0 0.86, 0.84, 0.84 0.85 0.76, 0.83, 0.76 0.78 8.23 2 0.81, 0.86, 0.81 0.83 0.62, 0.66, 0.62 0.63 24.09 4 0.90, 0.89, 0.85 0.88 0.82, 0.88, 0.89 0.86 2.27 6 0.91, 0.92, 0.95 0.93 0.80, 0.74, 0.81 0.78 16.13 8 0.92, 0.96, 0.94 0.94 0.92, 0.88, 0.82 0.88 6.38 10 0.95, 0.93, 0.93 0.94 0.92, 0.92, 0.89 0.91 3.19 Experiment 2 Sugar conc.(%) Mass Before (g) Av. Mass Before (g) Mass After (g) Av. Mass After (g) % Change in Mass 0 1.10, 1.00, 1.30 1.13 1.52, 1.52, 1.59 1.54 36.28 2 1.10, 1.30, 1.30 1.23 1.41, 1.38, 1.21 1.33 8.13 4 1.30, 1.20, 1.20 1.23 1.21, 1.23, 1.18 1.2O 2.44 6 1.10, 1.20, 1.20 1.16 1.01, 1.08, 1.21 1.1O 5.17 8 1.20, 1.30, 1.20 1.23 0.92, 0.99, 1.00 0.97 21.14 10 1.10, 1.10, 1.20 1.12 0.92, 0.90, 0.91 0.91 18.75 ANALYSING EVIDENCE AND DRAWING CONCLUSIONS: On the next page is a ...read more.


This experiment, instead of measuring a change in mass of the potato, a change in length of the potato could instead be measured. This would require a different method and equipment list. Weighing scales would not be required, as the mass is not being measured. Also, the results would be in an entirely different form and the graphs would produce different patterns and curves. Essentially the experiment would be much the same, with the same control, fair tests and safety, but it may produce a more accurate set of results to show the affects of Osmosis, Diffusion and Plasmolysis on a potato. I am not sure of my results, they are not what I expected to be and I certainly would not bet on them being correct. This is mainly because of the peculiar set of results shown on the second graph. My results cannot lead to a confident conclusion as they are inaccurate and of a poor quality. The data was reasonably accurate to some extent, considering that any number of the mistakes mentioned above may have been the cause of anomalies and inaccuracies in the results. The data also shows patterns of some sort, meaning that the experiment was not a complete failure, and that some conclusion can be drawn for this individual experiment, even though a general conclusion for Osmosis in general is impossible to make out from these results alone. ...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. Marked by a teacher

    How does the concentration of a sucrose solution affect the rate of Osmosis in ...

    5 star(s)

    I thought that if I was working out percentage change, this would not matter, but I now know that the size of the potato can alter the results, as can using a different potato. There is always natural variation, so some potatoes will lose or gain water more quickly than

  2. I am investigating the effect of osmosis on a potato. Osmosis is the diffusion ...

    This will allow us to see whether osmosis has taken place, and how much osmosis has occurred. The volume of the solution that the potato chips are kept in must be the same. The chip must be totally covered in the solution, and the amount of solution will be kept the same because all the chips are the same size.

  1. The Effect of Solute Concentration Upon the Rate of Osmosis

    0.4 1.415 1.4675 1.51 1.4275 1.3875 0.6 0.5825 0.58 0.57 0.5275 0.5175 1 0.5975 0.565 0.5275 0.535 0.465 Average Percentage Mass Change (%) Molarity Time in Minutes 0 10 20 30 40 0 0 5.182927 4.878049 5.182927 7.317073 0.2 0 0.438596 0.438596 -3.94737 2.192982 0.4 0 3.710247 6.713781 0.883392 -1.94346

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

    Molarity Sample Weight Original: New: Loss/Gain (g): Loss/Gain (%): Average Loss/Gain (%): 0.0m 1 1.17 1.34 + 0.17 + 14.53 +12.66 2 1.05 1.18 + 0.13 + 12.38 3 1.11 1.25 + 0.14 + 12.61 4 1.07 1.20 + 0.13 + 12.15 5 1.03 1.15 + 0.12 + 11.65 0.05m

  1. The Effect of Solute Concentration on the Rate of Osmosis.

    The water molecules in the solution and in the potatoes might also evaporate, a process I wouldn't be able to completely control. * Type of cell is vital in osmosis, because of the fact that the permeability of the membrane and the surface area of the membrane can be different

  2. Osmosis is the diffusion of water through a semi-permeable membrane, moving from a dilute ...

    The main flow of the water molecules is from left to right in the diagram and is very rapid in comparison to the opposite flow. Plant cells are made up of mainly salts, sugars and proteins, which exist in the cell's cytoplasm and the cell sap within its vacuole.

  1. Osmosis is the passage of water molecules from a weaker solution into a stronger ...

    using an electronic scale (for accuracy) and their individual masses recorded to two decimal places. The concentrations will then be made for the first stage (three of each concentration) and each test tube will be labelled with the concentration that it contains.

  2. Explanation on Osmosis and diffusion:

    Theory: In this experiment we will look at the rate of osmosis on pieces of potato. When plant cells are submersed in a solution of sucrose, the process of osmosis occurs. There are three things which could happen to the cell and it all depends on the concentration of the water in the solution.

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