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

An investigation into osmosis using a pealed potato and different concentrations of salt solution.

Extracts from this document...


Sheena Shah 11AL Osmosis in a Potato Chip Aim: An investigation into osmosis using a pealed potato and different concentrations of salt solution. Hypothesis: I predict that in this experiment, a higher concentration of salt solution will move to an area of low concentration of a solution. The definition of osmosis that the CGP Science Book gives is "Osmosis is the movement of water molecules across a partially permeable membrane from a region of high water concentration to a region of low water concentration." This means that if the potato is surrounded by a solution, which has a low concentration, the mass of the potato will decrease, as the high concentration from the potato will move onto the water, there for increasing the volume of water surrounding the potato. The partially permeable membrane in this experiment is the surfaces of the pealed potato. It will let the salt solution pass in and out of it, therefore increases or decreasing the mass of the potato. The GCSE Science Class book says, "Osmosis is a special type of diffusion. It occurs across a permeable membrane, which allows some particles to diffuse through it and not others. Most cell membranes are like that, being permeable to water and some solutes only." This means that the potato will definitely allow water to go in and out and should also allow the salt solution to enter it. I predict that the higher the concentration of the salt solution, the more solution will move out of the potato chip. Osmosis is the flow of a solvent of a solution, through a membrane. The membrane blocks off the other components so that they cannot flow through. ...read more.


* The type of solution that I use. A sugar solution would give different results to a salt solution. Therefore as I am using potatoes with salt solution in them, I will be using a salt solution too. Equipment: > A large potato > A measuring cylinder > A ruler > Weighing scales > 5 beakers > A potato borer > Salt solution- 0.5m, 1.0m, 1.5m, 2.0m, 2.5m > Stop clock > Knife > White cutting tile > Paper towels This is a diagram of the experiment I am carrying out. Safety: To keep myself safe during this experiment, I will make sure that the area I am working in is clean and safe, that there are not bags on the tables or on the floor which could cause an accident. When using the knife to cut potatoes, I will keep my fingers away from the blade. After I have used the solutions, I will wash my hands so that any excess solution will be washed away. Plan: * Collect equipment and place in a safe and clear working area. * Measure 75cm� of each solution using the measuring cylinder (0.5m, 1.0m, 1.5m, 2.0m, 2.5m) and pour into the beakers. * Use the potato borer to cut out 15 potato chips. Cut them to 4cm each using a knife, ruler and white tile. * Weigh each potato chip with the same weighing scales. Record the results. * Place three potato chips in each of the five solutions at the same time and record the time. By placing three chips in each of the five solutions, I can carry out three experiments at the same time, which will save time. ...read more.


This result may have been anomalous because of the room temperature. The temperature in the room could have varied and therefore affecting the result. Another reason for this anomaly could be because of human error. A mistake when measuring the potato could have occurred. The result could have been a mechanical error too, as when the potatoes were weighed; extra weight could have accidentally got onto the scales. The other results obtained were fairly accurate as I weighed the potatoes correct to 2 decimal places. If I were to carry out his experiment again, the main changes I would make would be to use a varied range of salt concentrations. For example 0.25m, 0.50m, 0.75m, 1.00m, 1.25m etc. This would give me accurate results and I would be able to find the isotonic point more accurately too. I would also use better equipment, such as a computerised weighing scale, which would give more accurate results. Instead of results 0.0g I would have results 0.000g. I would also try to find a machine that would cut the potatoes into exactly the same size chips. This would save time and make the experiment very accurate. I found that cutting the potatoes was the most time consuming. Another change I would make is to experiment with potatoes of a different type. These would have a different concentration to the potatoes used in this experiment and therefore would give me different results which I would be able to compare with the results from this experiment. Another variable I could investigate into would be the amount of solution used. Instead of using 75cm�, I would use more, such as 100cm�. This would tell me whether the amount of concentration used in the experiment varied the results or not. However, I am pleased with the set of results that I obtained and feel that this experiment has gone well. ...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

    To determine the water potential of a potato tuber cell using varying salt solution.

    5 star(s)

    Time The time that the potato is kept in the solution will affect how much water enters the potato cell and therefore effect how much the weight changes. If one potato is left longer than another obviously osmosis as more time to occur and so the change in mass will be inaccurate.

  2. Marked by a teacher

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

    4 star(s)

    > To make the experiment as accurate as possible an average will be taken out of the 3 sets of results taken. Therefore the experiment will be repeated twice., to gain an average. > As each test tube is filled up with the different molar solutions the syringe which would

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

    Another study done proves to be a good comparison for this investigation. According to Portnoy and Giblin (1997), in one study, scientists tried to reintroduce seawater into a diked salt marsh. However, the were unsuccessful. "The addition of seawater to highly organic, seasonally flooded peat caused the death of freshwater

  2. Osmosis investigation

    My conclusion matches my prediction well as I stated that mass is firstly gained and this gain decreases until equilibrium is reached and then mass is lost. I correctly assumed that mass increase would be the highest at 0.0m, where there is the lowest concentration and highest water potential, and

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

    > The Surface Area: This will speed up the time of osmosis because there will be more space on the potato for osmosis to take place. The equipment I used: 1) The tools: * 5 Test tubes with their holder. * A Forceps. * A Scalpel. * A Cork borer.

  2. Osmosis. I am going to do this experiment by placing potato chips into different ...

    Method: 1. Cut a potato into 12 equally sized chips without any skin 2. Accurately measure the weights of all 12 chips and mark them so that you know which one is which. 3. Measure out 50cl of each of the following concentrations of the salt solution using salt solution and distilled water.

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

    Evaluation My prediction was partly correct. The graph generally has a negative gradient, as I had predicted. I was correct in thinking that water would go into the cell from the solution because the solution was hypotonic to the cell.

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

    possibly have worked with someone, as I was working on my own, or even with the whole class. I could have also cut the potatoes into doughnut shapes, because the cells in the middle of the potato might have different properties, making them react differently to osmosis.

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