I will put different strengths of solution into five beakers and then put five equally cut carrots into the solutions. After five minutes I will weigh each of the carrots and then put them back into the beakers. I will do the same sequence every five minutes and record my results each time. I will weight them five times and then repeat the experiment to make sure my results are accurate and correct.
Hypertonic Solutions
These solutions contain a high concentration of solute relative to another solution. When an object is placed in a hypertonic solution, the water diffuses out of the cell causing it to shrink.
High – Solute
Low - Water
Carrot tissue
Hypotonic Solutions
These solutions contain a low concentration of solute relative to another solution. When an object is placed into a hypotonic solution the water diffuse into the cell causing it to swell.
High – Water
Low - Solution
Carrot tissue
Isotonic Solution
These solutions contain the same amount of solute as another solution. When an object is placed into isotonic solution the water diffuse in and out of the object at the same rate.
Basic Plan
For my experiment I will be using different strengths of solution to determine whether the weight of the carrot changes due to the occurrence of Osmosis.
I will use five test tubes; each with different strengths of solution in. below is a diagram of how strong each solution will be.
- Water
- Solution
Test Tube 1 - 100% Solution – 0% Water
Test Tube 2 - 80% Solution – 20% Water
Test Tube 3 - 60% Solution – 40% Water
Test Tube 4 - 40% Solution – 60% Water
Test Tube 5 - 20% Solution – 80% Water
Test Tube 6 - 0% Solution – 100% Water
I will start the experiment by cutting each carrot into equal sizes and weigh them to make it a fair test. Once the carrots are ready I will put them into each test tube and weigh them every five minutes.
To ensure that this is a fair test I will stop the clock each time I weigh a carrot. I will record the results and then repeat the experiment so that my results are reliable.
Equipment
- 6 Test Tubes – Make sure they are equally sized so that the experiment is fair
- Weighing Scales – Before we begin the experiment we need to measure the weight of each individual carrot. We then use the weighing scales in the experiment to weigh the carrots after we have had them in each of the solutions for different lengths of time. When using the weighing scales you need to make sure that they are always measuring things in the same units.
- Carrots and Corer – We need to use a corer to cut the carrots so they are all equally sized and weight. If they do not meet these requirements the test will be unfair and the results may vary.
- Stopwatch – A stopwatch is very important in this experiment because you need to know exactly when to weigh each carrot. If you do not weigh them at the right time the results will be incorrect and unfair.
- Solution and Water – When using the solution and water always make sure you know which one is which. If you don’t you may totally ruin the experiment and have completely wrong results.
Predictions
I predict that the carrot put into the test tube containing the strongest solution will be most affected by osmosis. This is because the molecules in the solution are larger therefore when they are absorbed by the carrot; the carrot will gain more weight. Due to the carrot absorbing the larger, heavier molecules the carrot will weigh the most and therefore be the most effected by osmosis.
Larger molecules
These molecules are larger because the solution is stronger.
I predict that the carrot put into the test tube containing the weakest solution will be affected least by osmosis. This is because the molecules in the solution are smaller therefore when they are absorbed by the carrot the carrot wont gain that much weight. Due to the carrot absorbing the smallest, lightest molecules the carrot will be least effected by osmosis.
Smaller molecules
These molecules are smaller because the solution is weaker
