Osmosis Lab

Osmosis is one of the most important regulators in the body. Osmosis regulates solvents through a semipermeable membrane from a less concentrated solution into a more concentrated one, creating equal concentration in and out of the cell. For the purpose of this laboratory a dialysis bag will be used to imitate the semipermeable membrane of a cell. The dialysis bags will be filled with different concentrations of sucrose and placed in distilled water to mimic osmosis. With the dependent variable being the mass of the bag and the independent variable being the sucrose.

Diffusion is a process in which material spreads through a liquid or gas evening out such as spraying perfume. Osmosis, a type diffusion, is the process of the movement of water

Fill the dialysis bag with water to test for leaks at a sink.

Step 5. Using the graduated cylinder measure 10mL of the assigned Sucrose solution.

Step 6. With another piece of string secure the other end with string segments.

Step 7. Rinse the outside of the bag under water and slightly squeeze the dialysis bag to check for leaks.

Step 8. With a paper towel once again gently, dry the outside of the dialysis bag.

Step 9. Place the dialysis bag on the scale and record the initial mass in grams.

Step 10. Return to designated lab station and fill the beaker with enough water to cover the dialysis bag then place the bag inside.

Step 11. Set timer for 30 minutes and allow osmosis to occur.

Step 12. After 30 minutes have passed remove the dialysis bag from the tap water and repeat step eight.

Step 13. Precede to measuring the weight of the dialysis bag in grams once again and record the data.

Step 14. Using the calculator, calculate the percentage of change by subtracting the initial mass from the final mass and multiply by 100.

Step 15. Record the data and precede to repeat the steps as instructed.

Step 16. Finally share and collect class data to compare accurate change of mass.

Data

Chart 1: Weight Change of Dialysis Bags in

It can be concluded that the dialysis tube was hypotonic due to more water entering the dialysis tube from the sucrose solution because how osmosis affects water. Water is attracted to the lowest concentrations of solutions and inside the dialysis tube was the lowest concentration. The dialysis tube allowed more later to enter causing a change in weight. A positive correlation is clearly shown, as the molar solution increased so did the mass of the dialysis bags. Group one were assigned tap water had a 2% increase in the weight of the dialysis bag. Groups two (.2M Sucrose solution), three (.4M Sucrose solution), four (.5M Sucrose solution), five (.6M Sucrose solution), group six (.8M Sucrose solution), and group 7(1M Sucrose solution) had increases of 10%, 12%, 7%, 13%, 11%, and 17% in weight.

Blunders An example of a blunders that might occurred include breaking glass and ripping the dialysis segments. The possibilities of human errors are also present in this experiment such as not adding enough water in the beaker or not securing the dialysis bag. Instrumental limitations include incorrectly measuring the sucrose solution and weight of the of each aspect. Errors due to external influences were present in this experiment; there should have not been any growth in the tap water dialysis bag but, there was due to something out of the control of the