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

Investigate the effect of varying concentration of sucrose in a solution on a potato cylinder of a given size.

Extracts from this document...

Introduction

An experiment to calculate the rate of osmosis in potatoes Skill Area P Planning Experimental Procedures Aim: To investigate the effect of varying concentration of sucrose in a solution on a potato cylinder of a given size Hypothesis: Osmosis is defined as the net movement of water molecules from a region of high water concentration, to a region of low water concentration, osmosis takes place across a partially permeable membrane, which only allows smaller molecules like water pass through it, and doesn't allow bigger molecules like sucrose to pass through. In this experiment the partially permeable membrane is the cell membrane of the potato cylinders. The water molecules will continue to diffuse until both sides of the partially permeable membrane have the same amount of water molecules and are equal- i.e. that there is the same amount of water molecules in the potato cylinder, than in the solution surrounding it. I predict that the lower the concentration of sucrose solution in the test tube the larger the mass of the potato cylinder will be. This is because the water molecules pass from a high concentration, i.e. in the water itself, to a low concentration, as there are more water molecules in the pure water solution than there is in the respective potato cylinder, due to osmosis the molecules will pass through into the potato, causing its mass to increase. ...read more.

Middle

- Stop watch Method: Prepare the 40mm potato cylinders with corer, ruler and scalpel, prepare the solutions (using syringe), blot (using tissue paper) the cylinders (roll for 5 seconds forward), weigh them, and record results. Using stopwatch, put respective cylinders in respective solutions (using china graph pencil to make sure we don't got confused, and time 25 minutes. After blot the cylinders, and weigh. Record results. Repeat method again for second set of results. Variables I am going to control To create a fair test certain aspects of the experiment will have to be kept the same whilst one key variable is changed. The key variable in this experiment is the concentration of the sucrose solution. If any of the non-variables below are not kept constant then it may influence my results, which would make this experiment an unfair test. For example if one of the potato cylinders was 50mm instead of 40mm, this could greatly influence my results, as then there is an extra 10mm of surface area for osmosis to occur. Below are the aspects I am going to control, as they could influence the experiment and make it an unfair test: - Temperature: by doing all tests in one room at a constant room temperature, as eat may cause a change in the kinetic energy of the molecules, thus speeding up the process of osmosis, and altering the amount of water molecules which may pass through the membrane, thus altering the mass of the potato cylinder. ...read more.

Conclusion

not to 0.00g but to 0.0000g. There were not any out of the ordinary results, but some were not as close to the line as others i.e. (2, -11.32), contamination or inaccuracies may have caused this. Also I felt that there must be another method of blotting, as I feel that I may have dried some more thoroughly than others, also next time I would have wiped the scales and my hands each time I came in contact with the cylinders, and perhaps this would have solved the anomalies on my graph. If the experiment was repeated, I could find another way to dry the potatoes that would ensure that all were dried in the same way for the same time. Also I had to use 3 different potatoes on different days, which may have affected the results as each potato has a different water concentration, perhaps I could conduct all the experiments using the same potato, or maybe be use a mention that measured water concentration- this would make my results far more accurate. However with all this said I think that the experiment was successful and I was pleased with the complete comparison of my results with my initial prediction. For further experiments I could measure how the varying concentrations of a sucrose solution affects the rate of osmosis on different vegetables; and see whether they reflect the results I obtained in this experiment. Anna Iqbal 10G 1/9 Biology Mrs Trustler ...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)

    The anomalous result could have even been down to something as simple as I drying it too much could, and even squeezing out a bit of water from the potato. As there are no other results that are that anomalous, I accept that it was probably a freak result that

  2. Marked by a teacher

    Investigating the effect of Sucrose Concentration on the Rate of Osmosis in Potato Chips.

    5 star(s)

    This is the concentration of sucrose solution when osmosis is not occurring because the concentrations of water are the same both inside and outside of the cell. Therefore water molecules do not move from inside or outside of the cell because the condition are exactly the same, this means that

  1. Marked by a teacher

    An experiment to investigate how the effect of varying concentrations of salt solutions play ...

    4 star(s)

    The calculations for both are shown below. Pre-made 2 Molar Salt Solution This substance already has the required amount of salt dissolved into the water to make it qualify as a 2 molar solution. To get lower molar values, the solution must have a certain amount of water added to it.

  2. Marked by a teacher

    Investigating the effect of sucrose concentration on osmosis in potato cells

    4 star(s)

    o I will measure the percentage change in mass to find out how concentration affects osmosis. I will do this by measuring the mass using a balance before and after the potato tissue goes in the sucrose solution and working out the percentage change.

  1. Marked by a teacher

    To investigate how varying the concentration of sucrose solutions affects the rate of osmosis ...

    3 star(s)

    If the cell is taken out at this point and placed in pure water it will still recover. 3. If the medium has a lower concentration of water than the cell (a very concentrated solution) the cell will lose water by osmosis.

  2. Experiment to find the concentration of sucrose solution where there is no change in ...

    using a white tile and scalpel. * Split them into 6 groups of 3 and find the mass of each group and mark them down. * Put three cylinders into each of the 6 boiling tubes with the solutions in, ensure that they are fully covered in the solution.

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

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

  2. To Investigate the Rate of Osmosis In Potatoes and Find Out the Sucrose Concentration ...

    The exact measurements of these variables needed to be decided upon on the basis of the preliminary results. Aim: To find out the range in which the concentration of the cell sap lay in by investigating the process of osmosis of pieces of potato in different sucrose solutions.

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