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

What affects the rate of osmosis?

Extracts from this document...

Introduction

Investigation: What affects the rate of osmosis The Problem Cathy works in a burger bar, making French Fries. She keeps the peeled chipped potatoes in water to stop them going brown before being cooked. She notices that they went soft if left in salt solution and hard if left in fresh water. Cathy needs to ensure that the chips are neither too hard nor too soft in order to make good French Fries for her customers. Factors that affect Osmosis Concentration of solution- it depends on the concentration of water in a solution to whether the potatoes will loose or gain water. Temperatures- the increase of temperature will make the water molecules; move faster so osmosis will happen faster. The size of the chip- the difference in surface area will effect how much water is lost or gained. The type of potato used for chip- each potato will have a different size of vacuole meaning that it can hold more water/less water than other potatoes Time the chip spends in a solution- the longer the chip is left in the solution the higher the chance of osmosis will take place. Introduction In this coursework I shall investigate what happens to the potato chips after they have been left in different concentrations of salt solution after a certain length of time. I will be comparing the various concentrations solutions with the potato chip to see if the concentration of a solution affects the rate of osmosis. ...read more.

Middle

that the size of the chips 3cm and the volume of solution, which was 5cm ,are appropriate and I wish to use the same amount of chip and volume of solution in the actual experiment. The distilled water gained mass (water) and each of the salt solution increased the loss of mass was greater. Looking for the osmotic potential I found that it must rest between distilled water and 0.5 salt solutions. Therefore I am going to repeat the experiment but using Distilled water, 0.1m, 0.3 0.4 and 0.5 salt solution. Fair test Given the mistakes made in the preliminary experiment there are a few areas where care is essential. There are also some constants, which must remain the same: * All of the potato slices must be placed in the solutions simultaneously. * All potato slices must be fully submerged. * All of the potato slices must remain in the solution for 48 hours. * The same potato will be used to bore slices out of. * Keep the temperature the same (room temp 23�C) * Make sure the concentrations are divided up carefully, using a measuring cylinder * Make sure the potato pieces are the same size Safety When conducting my experiment I will be making sure I don't harm my self or anyone else by always cutting up my potatoes on a ceramic tile. The use of the knife could be dangerous as there is a sharp blade. ...read more.

Conclusion

Problem with this method of experiment is that when we began the experiment the mass of each chip was not the same and neither was angle of each chip at the ends. I would also say that the chips and different amounts of time spent in each of the solutions, as they were not put into the solutions at the same time. The method we used to take of the excess water off was not accurate as we could have spent long on one individual chip, we could blot the chip too much or too less causing an anomalous results. To improve upon our method we may have used more potatoes to get the 18 chips as using just one potato meant that we had to be careful to not make mistakes when cutting the chips. We ought to have made sure prior the experiment that each of the chips mass weighed the same. We could have used a machine to cut the chips making the experiment a fair test and leaving no room for errors. We may have also rolled the potato chips on the paper towel a distance of 10cm for each, to remove the excess water. Furthermore we could have investigated between 0.1m and 0.2m salt solutions to find out exactly where the isotonic solution is, such as 0.11m, 0.12m, 0.13m, 0.14m and etc. We could investigate another factor for to work out an isotonic solution such as the type of potatoes used. ...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. 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 (%)

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

    My results did lie close to the curve, and therefore were fairly accurate, but if I was doing the experiment again I could make changes, some as mentioned above. I could also use a burette measure out my solutions. This would ensure that I have an accurate amount of fluid in each test tube.

  1. To investigate how different molar concentrations of a salt solution affects osmosis in equal ...

    The behaviour of the rate of osmosis will affect the appearance of my graph. My dependant data is the molar (or concentration) of each solution and my independent data is the change in mass and because I have predicted that as the concentration of my solutions increase the percentage mass

  2. How Osmosis affects Potato chips in different concentrations.

    these other factors like I mentioned below: The main factors which will need to be considered whilst doing the experiment are: * Temperature of water: Doing the tests at one fixed temperature will control the temperature of the water. For the purpose of my experiment I am going to do all the experiments at room temperature.

  1. Osmosis Investigation. To investigate osmosis I decided to test how the salt concentration of ...

    In concentrated solutions, water is sucked out of the cell by osmosis and the cell shrinks. Because of this animal cells must always be bathed in a solution which has the same osmotic strength as their cytoplasm. Animals which inhabit dry land or live in the sea must conserve water,

  2. What effect does the concentration of salt solution have on the amount of osmotic ...

    I shall fill the 6 test tubes labelled A-F with varying amounts of distilled water and salt solution. The quantities shall be: - Distilled Water Salt Solution A - 20 ml 0 ml B - 16 ml 4 ml C - 12 ml 8 ml D - 8 ml 12

  1. Investigation of different molar salt solutions on the rate of osmosis in potato slices.

    All other factors will stay the same. Type of potato-I must use the same type of potato throughout the experiment as different potatoes could have different densities. Also osmosis may occur at different rates in different types of potato. Temperature-The temperature of the potato and the room around it may affect the rate of osmosis.

  2. Investigate the effect of varying concentration of a certain sugar solution on the amount ...

    To understand how it works we can show how osmosis works around a plat cell. The above picture show what happens in a cell when the concentration of water is lower in the inside of the cell and the concentration outside of the cell is higher.

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