Diffusion Of Osmosis Lab Report

We set up 3 fermentation set-ups, labeling them 1, 2, and 3. Then, filled a tub with hot water and inserted the end of the plastic tubing into one of the test tubes and submerged the collection tube and plastic tubing in the tub. After that, we mixed the fermentation solutions for the other tubes, (tube 1 got 4mL of water and 3mL of corn syrup, tube 2 got 3 mL of water, 1 mL of yeast and 3 mL corn syrup, tube 3 got 1 mL water, 3 mL yeast and 3 mL of corn syrup) . We then mixed each test tube and put the rubber stoppers in the fermentation tubes. Finally, we marked the water level on each collection tube with a wax pencil to use as the baseline. Then at 5 minute intervals we measured the distance from the baseline for 20 minutes.

The experiment of the lab was to demonstrate knowledge of the concepts of diffusion and osmosis. Diffusion is the movement of substances moving from a high concentration to a low concentration. For this lab the rate of osmosis was measured in concentration. The concentration stayed the same and increased through the experiment. At the beginning of the experiment the sacs were weighed to determine the tonicity of water throughout the experiment. Timing was also a factor each 15, 30, 45 minute interval the sacs were weighed and recorded. Each sac had a different amount of solution in them. The tonicity of the sacs was determined as well by the final weights and the final percent of gain or loss of water in the sacs.

The Diffusion and Osmosis Lab determines the molarities of various sucrose solutions based on change in mass. Using table sugar in different amount of molar concentration 0.0M, 0.2M, 0.4M, 0.6M, 0.8M and 1.0M. The molarity of the solution of the sucrose solution in the dialysis tubing determines the amount of water that either move into the bag or out the bag, which also means its mass changed.

Using the graduated cylinder, measure 20mLs of the stock sucrose solution and 180mL of water to create a 3% sucrose solution and place it into the 250mL beaker (beaker #2). Place bags #1‐3 (red, blue, yellow) into beaker 2 and bag #4 (green) into beaker 1. Allow the bags to sit for one hour. After allowing the bags to sit for one hour, remove them from the beakers carefully open the bags, noting that often times the tops may need to be cut as they tend to dry out. Measure the solution volumes of each dialysis bag using the empty 250 ml beaker.

The hypothesis states that if the solution is hypotonic the results will decrease, if the solution is hypertonic the results will increase and if the solution is isotonic the solution will vary and or remain constant. In order to test the predictions of the hypotonic, hypertonic, and isotonic hypothesis for the solution  made during the study,  four samples of sucrose were taken and placed into two different beakers each containing a different concentration. Then dialysis tubing A was placed into beaker 1 with B, C, and D placed into beaker 2 for 45 minutes and weighted at 15 minute intervals. My finding in the study was that each of the four samples changed from their initial weight and for the most part accurately proved the hypothesis.

Next rinse the funnel with cleaning solvent to ensure all impurities in the solvent are removed.

When filling up the burette it is important that a funnel is used, however as the solution reaches the 0 mark it is ideal that the funnel be removed and a pipette used instead to reach the 0 mark, this is to achieve greater precision. During the experiment, it is important to swirl the flask continuously with one hand

Repeat steps 3-4: Fill 1 tube with 50% NaCl. Weigh each of the tubes/cells. Record on the chart. 3. Label a 500mL beaker with 50% NaCl and fill it with 400mL of the 50% NaCl solution.

1 ml of water should be added to the first test tube and make a note. In the second test tube, 1 ml of methyl alcohol should be added. In the third test tube, 1 ml of hexane must be added. Lastly, the fourth test tube will be a control.

Submerge the graduated cylinder in the plastic tub so that it is completely filled with water. Hold the open end of the graduated cylinder and move it vertically upside-down where the open end of the graduated cylinder is still submerged in the plastic tub. Clamp the graduated cylinder the ring stand of the lab table to keep it in place. perforate a hole in the top of the rubber cork for the solution container. Cut a straw the length of about four inches. place the straw inside of the rubber cork hole. Set up your timer for two minutes.

Cells are always in motion, energy of motion known as kinetic energy. This kinetic energy causes the membranes in motion to bump into each other, causing the membranes to move in another direction – a direction from a higher concentration of the solution to a lower one. Membranes moving around leads to diffusion and osmosis. Diffusion is the random movement of molecules from an area of higher concentration to an area of lower concentration, until they are equally distributed (Mader & Windelspecht, 2012, p. 50). Cells have a plasma membrane that separates the internal cell from the exterior environment. The plasma membrane is selectively permeable which allows certain solvents to pass through

5. Wet the paper with distilled water to hold it in place in the funnel. Transfer all the solution and the precipitate from the beaker using a rubber policeman. Wash the precipitate with two or three 5-mL portions of distilled water. Do this by adding each portion to the beaker in which you did the precipitation to transfer any remaining

Osmosis is a special type of diffusion. It is the diffusion of water across a semipermeable membrane which is a membrane that is freely permeable to water but is not freely permeable to solutes, the water moves from a dilute solution to a more concentrated solution (Karp, 2010). Both diffusion and osmosis are passive transport, energy is not used in the transport. In osmosis water moves across a membrane toward the solution of greater concentration, because the concentration of water is lower there (Martini and Bartholomew., 2007).

Measure the correct amounts of sugar and water into each of the labeled cups. One at a time, place a cup on the scale and add the sugar directly, but before you do so, hit the button “on” or “zero” to restart the scale. This way, the scale will only measure the amount of sugar that is poured into the cup and not the cup itself. The chart shown below will tell you how much sugar to weigh in each cup. Once you have finished, add 50 mL of water to each cup using the graduated cylinder. Then stir your cups with the spoon until the sugar has dissolved in each solution.

Collect to 2 large beakers both large beakers are to be filled with hot water (labtutor). Then obtain seven conical tubes these will be used to collect the levels of gas, you will also need test tube a stopper and a plastic tube (labtutor). You want to fill the conical tube to at least 50 ml of water (Cressy). Take the four conical tubes filled with water and place two in each beaker, to do this you must invert the tube and cover the release hole as to not lose any water (Cressy). Then place the beakers with the tubes in the bath so they can be at the same temperature as the bath (Cressy). Next mark all of your test tubes in number order to be sure which tube contains what concentrations and pH (Cressy). Having mixed a solution to the specifications of 2.5 ml of glucose in all tubes, 3 ml of yeast in 2 tubes of pH 5, 2 tubes of pH 9, and the single pH 7 tube, the remaining two tubes will contain no yeast as they will be negative controls. Next add 2 ml of pH buffer 3 tubes will receive pH of 5, three will receive a pH of 9 and a single tube of pH 7. Finally add pure water to make sure all test tubes have 10 ml of solution. When making the solutions