Egg Diffusion Lab
Looking at the class data, the mass and circumference of the egg in corn syrup reduced by an average of about 44.1% and 26.16% respectively, while the mass and circumference of the egg in deionized water barely changed at all. The circumference increased on an average of about 15.3% while the mass changed on an average of about 9.9% This change was caused when osmosis let water diffuse through the egg membrane, causing the egg to either swell or shrink. Corn syrup is hypertonic, while water is hypotonic. The corn syrup's solute concentration was higher, so water, the solvent, flowed out of the egg and passively diffused into the corn syrup, which had a lower water concentration. Thus, the egg shrunk. Conversely, when the egg was surrounded by deionized water, water flowed from the high concentration water around the egg and diffused to inside the egg, therefore making it swell.
The cell's internal environment changed depending whether vinegar, water, or corn syrup was added. When vinegar was added, the eggshell, made of calcium carbonate, reacted with acetic acid, dissolving it and leaving behind the broken down to make calcium ions and carbon dioxide. If water is added, osmosis occurs, and water passes through the egg membrane and causing the egg to swell, changing the internal environment of water-concentration and size. If corn syrup was added, then water passed through the egg membrane and into the surrounding syrup, causing the egg to shrink, changing the internal environment of the egg.
This lab demonstrated the biological principle that diffusion always wants to reach equilibrium. It demonstrates that osmosis will continue until equilibrium is reached, and continue to occur, just that there is no overall change in the concentration between the insides of the membrane and the surrounding environment.
This lab also applies to real life, too. Farmers sprinkle fresh vegetables with water at the markets, because water is hypotonic to the vegetables. The vegetables cells then absorb more water from their surrounding through osmosis, making the general size of them slightly bigger and more firm, becoming more appealing to buyers. The reason why roads are sometimes salted to melt ice is because when solutes are added to something like water, there is less vapor pressure, because there are less water molecules on the surface of the solution, thus there is less amount of water to change phases when in contact with the different environments around it. This reduces the freezing point of the solution.
Based on this experiment, I would test other things like vegetables or fruits, and calculating the different changes in size. I know that sprinkling water causes the vegetables to get firmer, but I would like to see if there is actually a significant difference in size if the vegetables and/or fruits were put in low-concentration or high-concentration water solutions for a long enough time.
This lab demonstrated the biological principle that diffusion always wants to reach equilibrium. It demonstrates that osmosis will continue until equilibrium is reached, and continue to occur, just that there is no overall change in the concentration between the insides of the membrane and the surrounding environment.
This lab also applies to real life, too. Farmers sprinkle fresh vegetables with water at the markets, because water is hypotonic to the vegetables. The vegetables cells then absorb more water from their surrounding through osmosis, making the general size of them slightly bigger and more firm, becoming more appealing to buyers. The reason why roads are sometimes salted to melt ice is because when solutes are added to something like water, there is less vapor pressure, because there are less water molecules on the surface of the solution, thus there is less amount of water to change phases when in contact with the different environments around it. This reduces the freezing point of the solution.
Based on this experiment, I would test other things like vegetables or fruits, and calculating the different changes in size. I know that sprinkling water causes the vegetables to get firmer, but I would like to see if there is actually a significant difference in size if the vegetables and/or fruits were put in low-concentration or high-concentration water solutions for a long enough time.
 |
| Weighing Egg after 48 hours in Corn Syrup Solution Photo Credits to Julia Yoo |
24 hour time lapse of our Egg Diffusion Lab. Egg on left in corn syrup, egg on right in DH2O pic.twitter.com/wdfujQyBXM— Mr. Orre's Class (@OrreBiology) October 5, 2016
Comments
Post a Comment