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

Investigation to find out the effect of osmosis on potatoes.

Extracts from this document...

Introduction

Investigation to find out the effect of osmosis on potatoes. Planning In this investigation I am trying to find out the effect osmosis has on potatoes. Osmosis is the passage of water through a semi-permeable membrane from a high water concentration to a low water concentration through a semi permeable membrane. The equipment we will use is as follows: - * 6 Boiling Tubes * 6 Pieces of Potato of a certain weight * 1 water and 5 molar solutions * 1 measuring cylinder * 1 potato borer * 1 balance/weighing scales. * 2 Test Tube Racks * 1 Stopwatch I will test 6 solutions, 0.2 molar, 0.4 molar, 0.6 molar, 0.8 molar, 1 molar and one that is totally water. The fixed variable will be time, as I will keep the potatoes in the water for 20 minutes each. I will keep the weight of each potato at 2.78g for each test. To ensure reliability and a fair test, I will make sure that the weighing scale is correct to 0.01g. ...read more.

Middle

Mass of potato at start (g) Mass of potato at end (g) Change in mass (g) Test 3 Test 4 Test 3 Test 4 Test 3 Test 4 0M 2.78g 2.78g 2.80g 2.71g 0.02g -0.07g 0.2M 2.78g 2.78g 2.72g 2.76g -0.06g -0.02g 0.4M 2.78g 2.78g 2.49g 2.56g -0.29g -0.22g 0.6M 2.78g 2.78g 2.45g 2.37g -0.33g -0.41g 0.8M 2.78g 2.78g 2.43g 2.41g -0.35g -0.37g 1M 2.78g 2.78g 2.25g 2.13g -0.53g -0.65g All of the results fit a pattern; they increase slightly for the water solution and then decrease gradually. The final set of results, however, do not fit this pattern. Analysis The change in mass graphs for all four tests have been drawn on separate sheets and can be seen later. The top reading did support my prediction as I predicted that it would increase from the starting weight and it did. I predicted the same for the second reading but this strangely decreased. My prediction for the bottom two readings was also correct as they decreased as predicted. ...read more.

Conclusion

Evaluation I believe that my results are quite reliable because we did repeat the tests three times after we had done the initial test. I found out that nearly half of my results turned out as I predicted, although many did not. My results were very consistent though, excluding the final set, so my prediction may have been wrong. The likely outcome is that the experiment went wrong. Perhaps the weight or length was very marginally different for those particular potatoes as the weighing scales could have had a problem, the water level might not have been quite the same, or the dilutions may have been slightly wrong. If we were to do the experiment again, I would try very hard to ensure that these problems would not happen again. As I said before, the 0M, 0.8M and 1M solutions supported my prediction, but 0.2M, 0.4M and 0.6M did not. To carry out further research, I could do the same experiment but with different foods or plants to see if that made any difference or I could put a raw egg into a small jar, fill it with vinegar and then see what effect it has on egg shells. ...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 Green Plants as Organisms 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 Green Plants as Organisms essays

  1. Marked by a teacher

    An investigation into the effect of a germination inhibitor on the germination of seeds.

    3 star(s)

    Note: The amount of water given to the seeds must be the same. If 5cm3 is given to one pot then 5cm3 must be given to all the pots, if this does not happen then it will be considered as an independent variable and could alter the results therefore they will not be based on just the inhibitor concentration.

  2. Investigate and find the water potential of baking potatoes and sweet potatoes in (N/mm2) ...

    You cannot use broken slices because they will have more surface area than a normal slice. Submerge the mounting needle (needle down) into the 0.0 mol solution. Then submerge the test tube into a water bath at 30�C. After 5 minutes remove it, roll it gently on some tissue to

  1. Investigate the use of Osmosis in potatoes

    The loss of water from the cell occurs because the water potential of the cell is smaller than the water potential of the solution therefore allowing the solution to win the tug-of-war so sucks water in from the cell making it shrink and become flaccid and plasmolysed.

  2. The Effect of Osmosis in potatoes.

    Step 6: Leave solutions for 25 minutes. Step 7: Take cylinders out, re-measure and re-weigh each potato cylinder. Step 8: Redo steps 1-7 two more times. Step 9: Pack up equipment Safety: I will make my experiment safe by following the class rules throughout the experiment such as not doing

  1. An Investigation into Species Diversity with distance along a Pingo.

    Scatter graphs correlating the abiotic factors with the SDI for each zone have also been included on separate paper. Two zonation chart graphs have also been drawn to show where each species was found along the pingo. The first shows a presence of above 1% of the species, however as

  2. Potato and Osmosis Investigation.

    a 1 molar solution, however we must divide this equation by ten so we get 34.2g in 100cm� of water. Preliminary Experiment: Before we begin our main experiment to this coursework, we conducted a preliminary experiment, this involved testing the rigidity of five separate 'evenly cut' pieces of potato chips

  1. Water moves from a high concentration gradient of water to a low concentration of ...

    Record the data and calculate the differences before osmosis occurred. 12. Repeat this for each experiment. Safety Issues We have to be always precautious at all times time prevent any fatal accidents. For example since we are using knives for cutting the potato we have to be precautious to ourselves and others.

  2. Osmosis investigation. My prediction is that as the concentration of the solute increases, ...

    1 core-borer (size to be used unknown as it depends on which one I can acquire)- a very good method of attaining similar samples of potato. Simply cutting bits off of a potato is vastly inferior to using a bore, because of the imperfection in my scalpel strokes making a borer more precise.

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