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

The effect of NaCl solutions on the mass of potatoes

Extracts from this document...

Introduction

The effect of NaCl solutions on the mass of potatoes Osmosis is a type of diffusion. It requires a concentration gradient and a semi-permeable membrane and, where the molecules of the solute are too big to pass through the membrane. Instead, the water is going to pass through the membrane in order to equal out the concentration of the solute. There are three types of solutions: * Hypertonic solution o A solution that has higher osmotic pressure (higher amount of solute) than another solution to which is compared * Hypotonic solution o Refers to any solution which has a lower osmotic (lower amount of solute) pressure than another solution * Isotonic solution o One that has the same solute concentration in both solutions With the help of this experiment, the best environment for the potatoes will be found. ...read more.

Middle

d. Move the water in the beaker around, so that the salt dissolves faster e. After the salt is dissolved, pour it back to the measuring cylinder f. Pour water until 50mL g. Pour 25mL of the water into one of the test tubes h. Label the test tube using the oil pen i. Repeat the steps b-h using 2g, 3g, 4g and 5g of salt (4%, 6%, 8% and 10% solutions respectively) 4. Put one potato piece in each test tube 5. Cover the top of each test tube with an aluminum cover in order to avoid evaporation 6. After 24 hours, take out the potato pieces 7. Gently dry the surface using paper towels 8. Measure the mass of the potatoes Variables: Independent variable: % solution Dependent variable: % mass change Controlled variable How? ...read more.

Conclusion

The % mass change decreased with the increase of the % salt solution. Possible errors and improvements * Possible errors o Potato pieces * First of all, not all of the pieces were perfectly rectangular, which could have affected the osmosis rate * Secondly, some pieces were not long/wide enough, some of them even had the peel on them * Improvements o Larger and sharper knives could have been used, in order to cut more precisely, or, instead, smaller potato pieces could have been used for the experiment Conclusion The data of all individuals followed the same general pattern, where the potatoes gained most mass in 0% solution, and lost most mass in 2% solution. The % mass change decreased with the increase of the % salt solution. This means, that potatoes grow best in hypotonic solutions, and they lose mass in hypertonic solutions. There were not a lot of sources of error, and those possible errors were avoided by several individuals doing the experiment. ...read more.

The above preview is unformatted text

This student written piece of work is one of many that can be found in our International Baccalaureate Biology 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 International Baccalaureate Biology essays

  1. The effect of concentration of sucrose solution on the osmosis in potato

    experiment is quite reliable and accurate, since the higher the Standard deviation the less reliable the results are. As the Standard deviation of 15% sucrose solution is only 0.67, it assume there may have some random error occur in the concentration of sucrose solution.

  2. The effect on osmosis on the egg shell

    These notable dissimilarities are visible on Graphs 1-6 which present results for each of measurements. Actually the greatest differences occurred for set in which egg was immersed in distilled water. It is also proved by the ranges shown in Tables 2-4.

  1. Isotonic Point of Potatoes

    and the ruler (+/- 0.05 cm) provided 4) Now pour 10.00 cm3 of the glucose solutions (0.10, .15, .20, .25, .30 M) into 5 different petri dishes using the measuring cylinder (+/- 0.05 cm3) 5) Place 5 potato strips of consistent length, height and breadth (size)

  2. biology extended essay - How different diets: vegetarian, vegan and a meat centered diet ...

    I still go to school even when I am sick Just About a day I still go to school even when i am sick I still go to school even when i am sick About a day or two How often do you exercise?

  1. Testing the solute concentration of potato cells

    This error goes with the uncertainties of measuring equipment. By the way, the uncertainties of 100 mL measuring cylinder is � 1 mL. Actually this much of uncertainties can have great effect as in maximum 2 mL less amount of sucrose solution, the osmosis reaction can not occur as well as in 2 mL more of sucrose solution, then

  2. The effect of toliet cleaning products on E-coli ...

    Venkat, pg 1, 2003). By this process all of the e coli bacteria would die in the zone of inhibition therefore no growth would be experienced in that sector, living cells would continue to grow surrounded in areas surrounding the zone of inhibition.

  1. What is the effect of different body positions i.e. lying down, sitting and standing ...

    and the control (sitting down) calculated in this experiment support the literature stated in the hypothesis, however the t-tests conduced reveal that these differences are not significant. This may have been the result of not leaving the participants in the different body positions for long enough for the blood pressure to change significantly or simply because experimental error occurred.

  2. Osmosis Experiment. This experiment is to consider how salinity influences osmosis in potato cells.

    Each of the options has different strengths and weaknesses. The biggest factors are about the amount of potato cubes to be used per investigation and how many potatoes per test tube. If the experimenter only cut a few pieces of potato per investigation, (option 1) it lacks in the accuracy of results.

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