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

How the concentration of salt-water affects the rate of osmosis.

Extracts from this document...

Introduction

How the concentration of salt-water affects the rate of osmosis. Aim: To find out how the concentration of salt-water affects the rate of osmosis in a potato. Prediction: My prediction is when the concentration of salt-water gets higher the mass of the potato will get smaller. The reason for this is because when the concentration of salt is low the concentration of water will be high. The water moves from a high concentration to a low concentration. The potato has a low concentration of water so the water passes through the semi permeable membrane and the potato gains water through osmosis, increasing the mass of the potato. If the concentration of salt is high then the concentration of water will be low. ...read more.

Middle

* The size of the potato because if they are different sizes the potato may gain more water because it can hold more making the test unfair. * The concentration of the salt in the water because the salt will affect how much water will move in or out of the potato. The apparatus I will need is: * Cups. * Different concentrations of salt-water. * A potato. * Something to cut the potato. * Electronic scales. * Coloured pins. * A ruler. * Measuring cylinder. This is what my experiment will look like. The concentration of the salt in the water is the one variable I am going to change because I want to find out how the concentration of salt-water affects the rate of osmosis. ...read more.

Conclusion

I will use five different concentrations of salt-water, distilled water, 0.25 M, 0.5 M, 0.75 M and 1 M concentrations of salt-water. The calculation I will do are the percentage increase in mass because they were not all the same mass when the were cut to size and to keep the test fair I will use the percentage increase to help me find out the relationship between the concentration of salt-water and the rate of osmosis. The graph I will plot will be a line graph to help show the relation ship between the two and to make the results clearer to see. I will make the results accurate and reliable by taking the average percentage increase from the results. I will take this by adding the three results from the one concentration and divide that by the number of results, which are three. ...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 Green Plants as Organisms 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 Green Plants as Organisms essays

  1. How temperature affects the rate of photosynthesis.

    3.22 mm3/min. This value is the same as one of the repeat values and the maximum variance from the results is that of 0.81 mm3/min only showing that the values are consistent. But some values like the results obtained at 35 oC are not very reliable owing to the large

  2. Water moves from a high concentration gradient of water to a low concentration of ...

    a concentrated solution we will measure the different types of solutions with the same measured amount of volume. In order to do this we need the following things to be done. Apparatus * 10 cm� 0 molar diluted sucrose solution * 10 cm� 0.5 molar diluted sucrose solution * 10

  1. Investigation into the relationship between the density of fresh water shrimps in fleet brook ...

    Dissolve oxygen level of water For all aerobic organisms, oxygen is essential for their survival. Thus, a higher concentration of dissolved will enable a larger population of gammarus to exist in an area providing other factors are not limiting. Control variables Nitrate levels in water This will increase the algal populations in the water.

  2. Determine the water potential of potato tuber cell with the varying affect of solute ...

    Instead of becoming turgid, the cell will become plasmolysed. This only happens in solutions with lower water potential then the cell. As the net movement of water goes out of the cell the protoplast peels away from the cell wall until equilibrium has been reached "Foundation biology" (Cambridge modular sciences 2001).

  1. Investigate the effect of salt concentration on the rate of water loss/gain by potato.

    Active Transport - The movement of substances through cell membranes, using energy. The energy is in the form of ATP, which is first made by respiration. The substances are often moved against their concentration gradient. Plant cell structure - Plant cells have a strong cell wall surrounding them.

  2. To determine how the concentration of salt water affects osmosis in potatoes

    Method - First the potatoes will be chopped into 1cm thick discs, 3 cm in diameter and weighed. They will then be placed in salt water for 10 minutes and osmosis will occur. We found in our preliminary work that this was the optimum time to leave them in for, because generally osmosis occurred much less after ten minutes.

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