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

The aim of this experiment is to investigate the effect that different concentrations of sucrose solution has on osmosis in potato chips.

Extracts from this document...

Introduction

Osmosis Coursework Aim The aim of this experiment is to investigate the effect that different concentrations of sucrose solution has on osmosis in potato chips. Scientific Knowledge Osmosis is the passage of water from a region of high concentration, through a semi -permeable membrane, to a region of low water concentration. A semi - permeable membrane (such as a cell wall) will allow small molecules such as water, Oxygen and Ammonia to pass through easily, but will prevent larger molecules, such as sucrose, starch and protein, from passing through. Osmosis generally tries to even the concentrations either side of the semi permeable membrane out, as shown in the picture to the left. This is also known as reaching equilibrium. Plant cells, such as those found in potatoes, can absorb water because the cell membrane is semi - permeable. When the cell absorbs the water it swells and becomes turgid. This is an essential in plant structure because it allows them to stand up by themselves without any aid. Eventually the pressure inside the cell will rise due to the excess amount of water and reach a point where no more will be able to enter. This is called hydrostatic pressure and it works against osmosis. Osmosis is an essential process in all-living things as it allows water to be passed from cell to cell, transporting it around the entire body or plant. When plant cells are placed in sugar solutions that have a lower content of water than the cell, the cells lose water and become flaccid. ...read more.

Middle

Results Concentration M 0 0.25 0.5 0.75 1 Mass before (g) 1.23 1.23 1.23 1.23 1.23 Mass after (g) 1.28 1.25 1.2 1.17 1.16 Difference (g) 0.05 0.02 -0.03 -0.06 -0.07 Percentage change 4.07 1.63 -2.44 -4.88 -5.69 Concentration M 0 0.25 0.5 0.75 1 Mass before (g) 1.37 1.35 1.35 1.35 1.35 Mass after (g) 1.47 1.38 1.35 1.39 1.31 Difference (g) 0.1 0.03 0 0.04 -0.04 Percentage change 7.29 2.22 0 2.96 -2.96 Concentration M 0 0.25 0.5 0.75 1 Mass before (g) 1.81 1.71 1.74 1.79 1.75 Mass after (g) 1.93 1.78 1.75 1.72 1.68 Difference 0.12 0.07 0.01 -0.07 0.105 Percentage change 6.63 4.09 0.57 -3.91 -4 To work out the percentage change I used the formula PC = Difference Mass before This will help me to put all of the three of the experiments into perspective and give them all a relative number. This will then allow me to calculate an average to get the most reliable result. So here is a table with the average percentage change for each concentration. Concentration (M) Average Percentage Change (%) 0 6 0.25 2.65 0.5 -0.62 0.75 -1.94 1 -4.12 I will now put this information into a graph to give me a better indication of any correlation that has emerged Analysing and considering evidence The graphs on the previous pages show simply that as the concentration of sucrose in the solution surrounding the potato increases the mass of the potato chip decreases. The fourth graph drawn was that of average percentage change across three experiments. ...read more.

Conclusion

However, the three individual experiments were carried out over a period of one week, running a risk of completely different temperatures and climates to work in. Additional experiments could be undertaken to investigate other possible factors affecting the amount of osmosis taking place in a potato chip. The first is that we could establish if temperature affects the amount of osmosis that takes place. I would do this by having two different concentrations of sucrose solution (such as 0M and 1M). Two potato chips would be submerged in 0M and 1M solutions at room temperature and two would be placed in heated solutions. After leaving them for a specified amount of time I would compare the weight after from the weight before. This would tell me whether the rate of osmosis can be changed by temperature and would also help me in the current investigation. I predict that in this investigation the temperature increasing would cause the rate of osmosis to increase. If the solution is heated, particles will be moving faster and reaching the semi-permeable membrane with more speed. The second experiment that could be undertaken is to investigate how different types of potato affect the rate at which osmosis occurs. No two types of potato will hold the same concentration of water molecules. If I were to investigate this I would use the same concentration of sucrose solution and five different types of potato, possibly with different origins. I would then leave the chips in the solution for a suitable amount of time before comparing the weight before and after. This further investigating may help to support my conclusion in this current investigation and may also help to explain the anomalies. Emma Lerway Biology Coursework 2003 ...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

    Investigating the effect of Sucrose Concentration on the Rate of Osmosis in Potato Chips.

    5 star(s)

    * Run the scalpel firmly along the ruler so that excess potato is severed from the chips that are now 5cm and will be used for the experiments. * Dispose of the surplus potato which has just cut and unneeded in the remainder of the experiments.

  2. Marked by a teacher

    An experiment to show osmosis in potato chips in different concentrations of sucrose solution ...

    3 star(s)

    * Pick out six of the chips, which are most suitable, and throw away any odd shaped potato chips. If there is any skin left on the potato chip you can remove the skin by cutting it off with a scalpel * Measure the sides of the potato chips so all the chips have relatively the same volume.

  1. Marked by a teacher

    To investigate how varying the concentration of sucrose solutions affects the rate of osmosis ...

    3 star(s)

    LENGTH: 4.50cm AVERAGE FINAL LENGTH: 4.18cm AVERAGE INITIAL MASS: 0.69g AVERAGE FINAL MASS: 0.52g The average change in length was a decrease of 4.50-4.18=0.32cm (-0.32cm gain) The average change in mass was a loss of 0.69-0.52=0.17g (-0.17g gain) Results: The prior test showed that water does move from places with high water concentration to places with low water concentration.

  2. To investigate the effect of different concentration of sucrose on osmosis in potato chips

    Measure mass and length, then leave for 40 mins. Then measure mass and length again. Preliminary results Concentration/M Length of potato chip/cm Mass of potato chip/g Change in mass/ g Before After Before After 0.0 5 6 2.92 3.38 -0.46 0.5 5 4 3.20 3.06 0.14 1.0 5 3 3.20 2.92 0.28 Explanation of how results helped in deciding

  1. The effect of sucrose concentration on osmosis in potato chips.

    cork-bearer, a cork-bearer allows me to remove a cylinder of potato tissue, I must not put the potato in my hand and then insert the cork-bearer as it may pierce through my skin. The precautions we took were: Whilst cutting the potato, extreme care and precision had to be taken

  2. An experiment to investigate the effects of sucrose solution on Osmosis in potatoes chips.

    Once the potatoes were wiped we weighted each one and write the answers down in our results table. Results: Concentration of Sucrose Solution (m) Mass at Start (g) Mass at End (g) Difference in Mass (g) Average in Mass Before (g)

  1. Experiment investigating concentration of sucrose solution and potatoes

    This graph shown above gives the line of best fit for the percentage change in mass of the potato chips over the course of the thirty minute experiment. The graph is a curve that slopes downwards and does not go through the origin.

  2. How Does The Concentration of a Sucrose Solution Affect The Mass of a Potato ...

    as clear a pattern as those for two days, as there may not be enough time for the chips to gain as much extra liquid as they are able to. However I will plot a graph of these results but I don't expect to see much of a pattern.

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