Observing Osmosis In Gummy Bear

In this lab we tested how changing the content of the water affects the speed of the alka seltzer dissolving. My hypothesis was that the tap water would dissolve the tablet fastest, the salt water would be second fastest, and the sugar water would be the slowest. I was correct that the tap water would dissolve the fastest, but I was wrong in that the salt water would dissolve faster than the sugar water. I think that our results came out the way they did because of the amount of sugar and salt we put into the water. When we put the sugar and salt into the beakers, we came up with those measurements on the spot. After the salt and sugar had been added, the salt water was very cloudy, but you could barely tell the tap water from the sugar water.

1. Why is it important to use distilled water instead of tap water used in Part 1?

If the gummy bear is added to the solution, then it will lose its coloring and expand.

The Osmosis and Diffusion lab was conducted to provide us with information on how built up mucus affects those conflicted by the recessive genetic disease, Cystic Fibrosis., due to a mutation to the membrane regulating chloride (Cl-). This mutation prevents the Cl- from leaving the cell causing the amount of sodium (Na+) in epithelial cells, which results in extreme mucus on the lungs and airways causing this disease to be fatal if not treated but treatment does not equate to a long lifetime. During the lab we took the data from three parts: Diffusion, Osmosis in an Elodea Cell, and finally the Role of Osmosis in Cystic Fibrosis. During Part 1 we looked at diffusion across a semipermeable membrane for starch and glucose, which resulted in both having a negative solution when placed in a semipermeable membrane. Then we looked at osmosis in the Elodea Cell to watch for the occurrence of Plasmolysis, when a cell’s plasma membrane pulls away from the cell, and how a plant cell is affected by both hypertonic and hypotonic solutions. Finally, we observed the role of Osmosis in Cystic Fibrosis using dialysis bags to represent a normal cell and a Cystic Fibrosis cell with the normal containing 1% NaCl while the Cystic Fibrosis bag contained 10% NaCl. After we ran the experiment, we looked at the Percent Change in Mass and compared them after 30 minutes. We found that Cystic Fibrosis cells didn’t change mass as much as the normal cell ending with a change in mass over -1%. The

If the hypothesis is correct, the masses after we place the tubing samples in water will be higher than the masses before. We will see the greatest % increase in mass in the highest concentration of sucrose (1.0 M). The % increase will get lower as concentration decreases. All of the samples should have some increase in mass because we are placing them in distilled water. Based on the known solutions, the data should yield a mathematical model relating concentration and % increase, which we can use to find the concentration of the unknown solution.

For my experiment I picked 3 different brands of bubble gums. Hubba Bubba gum, Bubble Yum and Bazooka. After chewing each piece of gum for 2 minutes, one at the time, I blow a bubble as big as I could. Then, my partner (my mom) measured and I write down the results. I repeated the same steps 3 times and results was collected in a data chart (see data chart # 1). Then, the average size of the bubble was calculated by adding each result and divided by 3. The average size of the bubble made from Hubba Bubba Gum was 3.8 cm, Bubble Yum was 3.5 cm and Bazooka was 3.3 cm. As a result of my experiment, I found that Hubba Bubba gum makes the biggest bubble (3.8 cm).

Though the theory following the hypothesis is correct and the experiment was carried out with as much attention as possible in a high school laboratory, the results obtained were still indicative of a few errors and did not support the predicted hypothesis. From the results obtained it can be concluded that as the concentration of sucrose increases the average percentage change in mass decreases. This is because the salt concentration inside the potato cubes of 10%, 15% and 20% concentration is less that in the salt concentration on the sucrose solution, thus the three cubes submerged in the 10% - 20% concentrated solution lost mass (hypertonic). However the cube submerged

The density decreases. Density of the liquid sample is the mass divide by the volume. If the mass stays constant and the volume increases then the density of the liquid sample will decrease.

The major objective of the experiment was to test the effect of the concentration gradient on the diffusion rate. It was hypothesized that the greater the stronger the concentration gradient, the faster the rate of diffusion would be. To test this, dialysis tubes were submerged in different concentration fructose solutions. We weighed the tubes at specific time intervals to measure the rate of diffusion of water in each different solution. The results illustrated that increased concentration gradient increases the rate of diffusion of water in the tubes. We concluded that as concentration of the

Osmosis is defined as the tendency of water to flow through a semipermeable membrane to the side with a lower solute concentration. Water potential can be explained by solutes in a solution. The more positive a number is more likely it will lose water. Therefore should water potential be negative the cell the less likely it will lose water. In using potatoes the effects of the molarity of sucrose on the turgidity of plant cells. According to Clemson University, the average molarity of a White potato is between .24 M and .31 M when submerged in a sorbitol solution. This experiment was conducted with the purpose of explaining the relationship found between the mass in plants when put into varying concentrations of sucrose solutions. Should the potatoes be placed in a solution that contains 0.2M or .4M of sucrose solution it will be hypotonic and gain mass or if placed in .6M< it will be hypertonic and lose mass instead. Controlled Variables in this lab were: Composition of plastic cups, Brand of Russet Potatoes, Brand of Sweet Potatoes and the Temperature of the room. For independent variable that caused the results recorded it was the different Sucrose concentrations (0.0M, 0.2M, 0.4M, 0.6M, 0.8M, 1M). The dependent variable was the percentage change from the initial weighs to the final. The cup with .4 molarity was the closest to an isotonic solution and was used as the control group for the lab. Water potential is the free energy per mole of water. It is

The one candle got the water to rise up 1 inch and a half, two candles rose ¼ of an inch and the three candles got the water to rise up ¼ of an inch as well. Because of the results it was hard to match it with an explanation but the closest it supported was explanation 3 because of the water still rising a bit than nothing. Since more candles mean more carbon dioxide being created we came to conclude that there might have been CO2 molecules dissolving in the water causing it to rise a bit. The experiment disagreed with explanations 1 and 2 because there was no pressure in the outer of the flask to cause the water to rise up and the water barely rose which causes it to be that what should have caused the rising was the CO2

3. Q-Thinking about what you learned in the lab and doing some additional research, if you mixed fresh and salt water together in the marine environment, how would the water “layer”? Where would the freshwater be and why?

Osmosis is a special type of diffusion where water molecules move down a concentration gradient across a cell membrane. The solute (dissolved substance) concentration affects the rate of osmosis causing it either to speed the process up or slow it down. Based on this, how does different concentrations of sucrose affect the rate of osmosis? If sucrose concentration increases in the selectivity-permeable baggies, then the rate of osmosis will increase.

Hand out from the Natural Science Establishment, six dialysis tubing, six plastic cups, distilled water, 0.2 M, 0.4 M, 0.6 M, 0.8 M, and 1.0 M samples of a sucrose solution, paper towels, and a scale.

The independent variable of this experiment were the different types of the solutions used, while the dependent variable was the mass of the cucumber slices. The constants were, the amount of liquid used and the time the cucumbers were left in the solution. While the control was the cucumber left in the cup with no solution. The students made a hypothesis saying that they believe that the cucumber slices put into the salt solution would decrease in mass while the cucumber put in the distilled water would increase in mass. In the end, the results of the experiment supported the students