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

The aim is to find out how osmosis is affected by different concentrations of salt solution, in potato tissue.

Extracts from this document...


An investigation to see how OSMOSIS is affected by different concentrations of salt solution!! AIM: the aim is to find out how osmosis is affected by different concentrations of salt solution, in potato tissue. Diagram: [image004.gif] [image005.gif] [image006.gif] Bung salt solution test tube Potato chip [image007.gif] [image008.gif] [image008.gif] [image008.gif] [image008.gif] [image009.gif] Distilled 0.25% 0.5% 0.75% 1.0% Concentrations of salt solution Safety: v Tie your hair back - because loose hair can interfere with practical work. It might dip into acid etc. v No running- because this will cause lots of accidents, there is more chance of slipping and you may bump into other people. v Clear up any spillages - because other people can slip and some substances can be harmful. v Stand up - so that if there is a spillage or explosion it is easier for you to get away. v Tuck stools under tables - so that people don't bump into them. Equipment: v Test tubes X 15 bungs X 15 v Borer measuring cylinder v Test tubes racks tile v Ruler scales v Knife tissue v Plain sticky labels potato v Five different concentrations of salt solution. The input variable for this investigation was the different concentrations of salt solution. ...read more.


There are no specific patterns in the way osmosis occurred. For example as the concentration doubled the change in mass did not halve or anything like that. The reason for this is that in the pure water solution the potato chips swell up because water enters them by osmosis, in the rich salt solution water leaves the potato chip by osmosis, and so they shrink in size. Osmosis is trying to balance the amount of water particles on each side of the partially permeable potato membrane. When there is hardly any salt in the salt solution (i.e. it is weak) there is more water in the solution than in the potato so water goes form the solution into the potato. When the salt solution is more concentrated (i.e. 1%) there are more water particles in the potato than in the solution so they leave the potato and enter the solution by osmosis. If you think very technically then there should be a pattern that as the concentration doubles the change in percentage mass should halve. Because at 0.25% there was a + 13% mass change, at 0.5% there was an + 8.8% change, which is nearly half. In the 0.5% salt solution there are twice as many salt particles than in the 0.25% solution, this would mean that there would there is less water in the 0.5% salt solution and therefore less osmosis is needed to reach a water Equilibrium. ...read more.


Also to get very definite end results the experiment could have been left for longer so that all the osmosis that was going to happen would have happened. A water equilibrium would have been reached, and then the mass of the potatoes would be in some sort of proportion to the concentration of the solution and it may have also been possible to come up with a formula or rule that linked the two. This investigation could have been extended for a different variable. Many things affect the rate at which osmosis occurs like, the concentration gradient, the size of the ions or molecules, and the distance over which it occurs. It is possible to extend this particular investigation by using a different substance instead of the potato. Some thing with a much thicker membrane would increase the distance over which osmosis has to occur and consequently the results would be different if the experiment was left set up for the same period of time. This investigation would then be to see what factors affect the rate at which osmosis occurs. Alternatively an investigation could be carried out to see how temperature affects the rate. This could be done by setting up the experiment in the same way as before but instead of simply leaving the test tubes to stand in a test tube rack; they could be put into water baths that are kept at certain constant temperatures. ...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. An investigation into osmosis using a pealed potato and different concentrations of salt solution.

    They will all have to have salt solution in them, as this is what I will be using in the experiment. I will also have to make sure the length and surface area of the potato are kept the same.

  2. Osmosis. Aim ...

    First set of results Concentration of Solution (%) mass before (g) mass after (g) Percentage Change in mass 20 1.73 1.87 8.1 40 1.7 1.67 -1.76 60 1.67 1.61 -3.6 80 1.55 1.35 -12.90 100 1.62 1.39 -14.2 Second set of results Concentration of Solution (%)

  1. Investigate the osmosis in Potato rods when they are put in different Concentrations of ...

    I will prepare the salts and pour them into the test tubes by using the gas syringe. 4) After preparing the concentrations of the solutions I prepared the potato and I brought the Cork borer and cut from the same potato 10 rods of potatoes that were not equal in length.

  2. Investigation Into How Osmosis In Potatoes Is Affected By Solution Concentration.

    It loses its turgor and becomes flaccid. If the external solution is strong enough, the cytoplasm eventually pulls away from the cellulose wall in what we call plasmolysis; I do not expect this to occur in this investigation, as the solutions I will be using will not be strong enough

  1. How Osmosis affects Potato chips in different concentrations.

    Then weigh them straight away to stop the sample losing any more water that would produce inaccurate results. The two variables in this experiment would be the different molarities of the sugar solutions and the changing weight of each potato sample.

  2. An investigation to find out the effect of salt solution concentration on potato tissue.

    1m 1.8g 1.7g From preliminary results table 1, I can see that the practical was a success because chip one's mass increased as it was in pure water 0m salt solution, where as chip two's mass decreased as it was in 1m salt solution.

  1. I aim to find out at what strength of salt solution there is not ...

    In petri dish 5 I will have 0.4 molar, in the last petri dish I will have0.5 molar salt solution. So there is a whole range of different concentrations. RELIABLITY To make my experiment reliable I shall conduct my experiment twice to make sure that my results match up.

  2. I aim to find out whether osmosis happens in potatoes, and how different water ...

    Preliminary Test I wasn't sure how much potato to use so I set up a preliminary test which would be designed to test which size of potato would give the largest reaction. The two main variables in this test where the thickness of the potato and the length of the potato.

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