Osmosis and Molarity Experiments

Egg Osmosis

The purpose of this experiment was to model the movement of water when an egg is placed in solutions with different levels of solute.

Materials: Purified water, vinegar, food dye, syrup, egg

24 hrs IN water

First, we placed the egg in 100 ml of water for around 24 hours. Above is the picture of the egg after it was in the water. As you can see, the egg has become more transparent and grown in size. It also developed a squishy feeling.

Egg Outside the Cup

Above is a photo of my partner and I weighing the egg after its time in the water. It grew in mass.

24 hrs in Syrup

Next, we placed our eggs in corn syrup and covered them with something heavy enough to hold them down. We let this egg sit for about 24 hours and then observerd thee results. Above is the egg after its time in the syrup; the egg is wilted and smaller in mass/size.

24 hrs in Colored Water

Last, we placed our egg back into 100 ml of water mixed with a chosen dye. We let the egg sit in the water for around 24 hours and noticed the original size and shape returning to the egg, along with another characterisitc; an orange tint.

Egg Outside the Cup

This is the final egg outside the cup. Its size/shape has returned, but the egg is still squishy, slightly transparent, and orange. The final weight was less than the original weight of the egg.

Gummy Bear Experiment

The purpose of this experiment was to see how different concentrations of sugar in water affected gummy bears.

Materials: 2 gummy bears, salt, spoon, cup, purified water

Original State

We had two gummy bears, one in 100 ml of water (pictured to the far left) and the other in a solution of 100 ml of water and 6 grams of salt (pictured to the far right).

24 hrs in Water

After letting these gummy bears sit for around 24-48 hours, the water gummy bear grew exponentially in size. It lost a lot of its color and was super sensitive to movement.

24 hrs in Salt

This gummy bear was the bear in a solution of water and 6 grams of salt. The gummy bear slightly grew in size and lost some of its vivid color. The reason the gummy bear grew even though their is solute in the solution is because the solute concentration is higher inside the gummy bear than out. This means the water will still move into the gummy bear.

Carrot Molarity Experiment

The purpose of this experiment was to see how difference concentrations of sugar in water effected the carrots color and size.

Materials: Purified water, sucrose (liquid sugar), cup, carrots

Original State

We took eight similar sized carrot slices and placed four in 100 ml of water and 4 in a solution with 110g of sugar.

24 hrs in Water

This is the group of carrots in the water after about 24 hours. We observed the carrots were basically the same size as before but looked like were more hydrated.

24 hrs in Sucrose

This is the group of carrots in the solution with sugar after about 24 hours. These carrots looked dehydrated, a more vivid and deeper orange, and shrunk/loss mass.

Graphing Table(s)

Carrots

Above is the graph of our classes combined recordings of the mass before and after the carrots soaked in the two solutions.

Gummy Bears

Above is the graph of our classes combined recordings of the mass before and after the gummy bears soaked in the two solutions.

Reflections

Egg - I learned that when the egg gained mass in the distilled water, lost mass in the corn syrup, and regained mass and color in the dyed water. This demonstrated the movement of water across a selectively permeable membrane and how an egg reacts in hypotonic and hypertonic environments.

Gummy Bear - I learned that gummy bears expand in distilled water and remained similar size in MY concentration of salt because it already contains a similar amount of solute.

Carrots - The carrot pieces gained mass in low sucrose molarity and lost mass in high molarity. This is why my carrots in water remained the same size and the carrots in sucrose shrunk.

Active Transport

Active transport is the net movement of molecules against the concentration gradient. In active transport, the concentration goes from low to high. It requires metabolic energy to move large, polar, or charged molecules. Molecules are often transported with the help of protein channels, such as a sodium-potassium pump. In the picture above integral protein, which are fully or partially embedded proteins used for cell signaling, are being used to transport glucose through the lipid bilayer.

Simple Diffusion

Simple diffusion is a form of passive transport, which is the net movement of molecules with the concentration gradient, from high to low. Passive transport moves smaller atom/molecules, such as water through the process of osmosis, across the cell membrane naturally. This diffusion does not use metabolic energy. Placed above the lipid bilyaer is a peripheral protein. This protein facilitates reactions and communication using signal receptors and messages. They also provide support by attaching to the cytoskeleton.

Facilitated Diffusion

Facilitated diffusion is another type of passive transport. In facilitated diffusion, molecules still follow the concentration gradient, but with the help of a protetin. Channel proteins are often used in facilitated diffusion to guide the larger molecules through the lipid bilayer smoothly and safely.

Macromolecule Card Sorting

To the left, we worked in groups and matched the characteristics of each macromolecule to its respective group.

Macromolecule Lab

Explored how the joining of compounds to different substances affected them.

Properties of Water Lab

In this lab, we used celery, water, and food dye to test the properties of water and how they work. The specific properties of water we saw in action here are cohesion, the attraction of water molecules to each other, and adhesion the attraction of water molecules to another molecule. These two properties used together in this experience is called capillary action, which is when cohesion keeps the water molecules together as they travel up the xylem and adhesion sticks the water molecules to the inside of the xylem, allowing for its nutrients to spread inside. This is what caused the color change of the leaves, as they were taking in the red food dye from the water as well.