• 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

The effects of different salt solutions on potatoes

Extracts from this document...

Introduction

The effects of different salt solutions on potatoes Plan My aim is to investigate how different concentrations of salt solution affect the movement of water through a partially permeable membrane (osmosis) in potatoes. Osmosis is the movement of water from a high concentration to a low concentration through a partially permeable membrane. I will add pieces of potato to varying concentrations of salt solution, wait on each solution and then record the results. I will eventually use the results to measure the percentage change in mass of the potatoes. To gain accurate results, I will have to make the experiment a fair one, to do this I will implement the following: Wash my hands before preparing any potato samples. -So no grease, dirt or any salts transfer from my hands to the potato pieces before the experiment takes place. I will take core samples from the potatoes. -To ensure maximum surface area for the salt concentration to cover. Make sure that only my variable factor changes throughout the experiment and other factors stay constant. Wash all equipment before using them - To make sure no residue left on them affects the results. There are several factors that would affect my experiment, the paragraphs below identify these factors and explain how I will keep them constant. - My variable factor for the experiment is the salt solution. I am aware that the experiment will be affected by certain factors; I will try and keep these factors constant so the end results will be accurate and therefore conclusive. Surface area would affect the rate of osmosis because the greater the surface area the more area the water has to diffuse through. ...read more.

Middle

9. I will then analyse and evaluate the whole experiment. I will repeat the experiment 3 times in order to get a more varied set of results, which will be more useful in showing the results to be accurate. I will leave the potato cores for 180 minutes because I believe that leaving them for any shorter period would mean that osmosis would not have happened fully and therefore I would get inconclusive results with a large margin of error. My range of concentration will be from 0% salt solution to 1.8% salt solution. Safety Even though this is a fairly safe experiment, safety precautions must be taken in order to prevent physical damage to the body. Be cautious when using the scalpels or corers as there are sharp metal edges exposed. In case of any breakages of the glass beakers, the teacher must be informed straight away and the glass cleaned away as quickly as possible. Syringes must be used safely and only used inside measuring containers to extract or deposit solutions. The table below shows the concentrations of water and salt solution in 10 concentrations. Final concentration of 20ml3 salt solution% Volume of water ml3 Volume of 2% salt Solution ml3 0 20 0 0.2 18 2 0.4 16 4 0.6 14 6 0.8 12 8 1.0 10 10 1.2 8 12 1.4 6 14 1.6 4 16 1.8 2 18 Results For 1st experiment Concentration Of salt sol. % Diameter of potato Change in Diameter of potato mm % change in diameter of potato Time=0 Full time 180mins 0 11.1 11.1 0 30 0.2 11.2 11.65 0.45 65 0.4 11.8 12.3 0.5 10 0.6 11.5 11.1 0.4 10 0.8 11.6 11.8 0.2 -25 1 11.9 11.3 0.6 -150 1.2 ...read more.

Conclusion

Also, because of the safety measures that I used (like washing my hands and all equipment before use) - I was able to decrease the margin of error and therefore increase the accuracy of the results. I know that my method must have been a fairly good one because of the accuracy of the results and how they agree with my conclusion. The prediction agrees with the results as well as the conclusion, so I know that the results must be fairly accurate. Apart from the general margin of error that meant that none of my graphs were completely similar, there was one very erroneous result taken on the 3rd experiment (circled on the graph). I think that this could have happened because all cores were not completely cylindrical, the diameter varied at different points along the sample. This would have meant that readings might have been taken from different points along the core before and after the experiment - giving inaccurate results. Because of the nature of the thing I was trying to measure (potato cores) and the difficulty of being completely accurate, it has led me to believe that maybe measuring another factor that would have changed as a result of different salt concentrations like the mass of potato cores. This would have given me more accurate results, as there wouldn't have been any problem with measuring by hand at different points. Also, digital scales would have preformed all measuring, which would have been far more accurate. To reduce error on measuring the diameters of the potato, I could have taken at least 3 diameter readings from each core and found the average diameter size to use in my results, but this would have been too time consuming under the circumstances. ...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

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

    4 star(s)

    the results, we see that as the molarity increases, the percentage difference decreases and with very high concentrations becomes a negative value. However I have found an anomaly of 0.5 M which has dipped to a negative value of percentage difference.

  2. Lab Research Paper. Just a Pinch of Salt and a Dash of Bacteria: the ...

    In fact, a study was done by Torzilli (1997) and a group of scientists where they found that a fungus, Aureobasidium pullulans, lived in a symbiotic relationship with the vegetation around them. Aureobasidium pullulans is a yeast-like fungus that can be found in many different environments such as soil, water, air, and limestone.

  1. 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.

  2. Use scientific knowledge and practical skills to determine the effect of a range of ...

    the water will go out of the potato and into the liquid solution, as osmosis is the movement of water molecules from a region of high concentration to a region of low concentration, through a partially permeable membrane. The potato, cut up into pieces, will need some sort of element

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

    somebody might make a hole in the clingwrap. EQUIPMENT LIST I am going to need. All equipment can be found in the school lab: 1. A chipper - To get chips of equal dimensions from the same potato to make it a fair test, plus it is quicker than using a knife to cut all of it. 2.

  2. Investigating the effects of submerging potato tissue in different concentrations of salt solution

    work will affect my plan From my preliminary work, I have decided to change some factors for my next experiment. The first is that I am going to cut the length of my potato cylinders from 7.5cm to 4cm. This is because it is important to use the same potato (see variables table)

  1. To find out the effect of changing the concentration of different solutions in which ...

    * Weigh the potatoes and write down the results. * Pour the volumes of the different concentrated solutions into labelled boiling tubes and places these tubes in a boiling tube rack. * With a paper towel, pat the potato pieces so as to remove any excess water before they go into the different solutions.

  2. Investigation to see how Concentration affects the rate of Osmosis on Potatoes.

    The diagram below illustrates how water is taken out from a dilute solution inside the cell to a concentrated solution outside the cell. Water Molecule In plant cells, the cytoplasm and the cell sap in the vacuole contains salts,

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