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

Osmosis Investigation

Extracts from this document...

Introduction

Osmosis Investigation Aim: To investigate the effect of varying concentration of a certain sugar solution on the amount of osmotic activity between the solution and a potato chip of a given size. Osmosis is defined as the net movement of water or any other solutions molecules from a region in which they are highly concentrated to a region in which they are less concentrated. This movement must take place across a partially permeable membrane such as a cell wall, which lets smaller molecules such as water through but does not allow bigger molecules to pass through. The molecules will continue to diffuse until the area in which the molecules are found reaches a state of equilibrium, meaning that the molecules are randomly distributed throughout an object, with no area having a higher or lower concentration than any other. Equipment list * Potato borer * Boiling tube rack * Boiling tubes * Paper towels * Weighing scales * Knife * Test tubes Prediction: For this particular investigation I think that the lower the concentration of the sugar solution in the test tube the larger the mass of the potato will be. This is because the water molecules pass from a high concentration, i.e. In the water itself, to a low concentration, i.e. ...read more.

Middle

I had to be very careful whilst cutting the potato as the borer is exceptionally sharp. I then had 10 which weigh roughly the same mass. * Taking a test tube rack I placed 5 test tubes and then labelled them 0 molar, 0.2 molar, 0.4 molar, 0.6, 0.8 molar and 1 molar. * I swiftly put 1 chip into each boiling tube. * Whilst waiting I set out some paper towels with which I was going to dry the paper and I drew up a basic table for my results. * After 24 hours I drained out the solutions in the sink and placed all the chips on the paper towel in the order I had put them in the test tubes as to not confuse myself as to which chip came from which solution. * I dried each chip with the paper towel and then placed each one on the scales so that I could weigh them. * Each potato was measured accurately on the electronic scales and then the weights were recorded. Analysis From my graph I can see that osmosis took place in the potato. I know this as there was an increase and decrease in mass. From the graph you can see that the isotonic point is between a sugar concentration of 0.2 and 0.4. ...read more.

Conclusion

There were one anomalie result, and some were not as close to the line as others. This could have been caused by human error. When the potato chips were removed from the test tubes and dried I may well have dried some potatoes more thoroughly than others and so some would have more excess water, which would add to the mass. 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. However with all this said I think that the experiment was truly successful and I was very pleased with the complete comparison of my results with my initial prediction. To further this investigation I could try to find the exact isotonic point as from my graph it shows me that the exact point is somewhere between 0.4 and 0.6. To achieve this I would use a range of concentrations between 0.2 and 0.4 the concentrations I would use would be: 0.4., 0.42, 0.44, 0.46, 0.48, 0.5, 0.52, 0.54, 0.56, 0.58 and 0.6. These concentrations of sugar are so precise I would then be able to find the exact isotonic point. I would create a graph which would look the same as my previous graph just zoomed in with increased concentration recordings, the recording exactly on the line would be the exact isotonic point. ?? ?? ?? ?? Lloyd Walton 11CF ...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 ...

    have all been cut without being washed and peeled. * The surface area, diameter, length of each potato chip must be the same. If it was different then the rate of osmosis will differ for each potato chip. The larger the surface area, width and length of the chip, the quicker the rate of osmosis.

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

    osmosis takes place � Balance � to weigh the potatoes � Cork borer � to cut out potato cylinders Planning Before actually planning the experiment, I will do some research to find out about osmosis, and matters related to it, so that I can make predictions.

  1. Osmosis Investigation

    if I do not, then the cork borer may cut through the hand. - When cutting the potato tubors to equal length of 4 centimeters, I will make sure to hold it from the blunt end and be careful not to cut my fingers.

  2. Osmosis investigation

    Calculate the Mass change by subtracting the 'mass before' from the 'mass after'. Write down the results in the 'mass change' column of the results table. Now you can calculate the percentage mass change, dividing the mass before by the mass change, then multiplying it by 100, does this.

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