Diffusion and Osmosis
Molecules are always in constant movement. Molecular motion is a form of energy, the kinetic energy of molecules. The Brownian movement is the movement of small particles caused by the bombardment of the particles by millions of water molecule. This movement will continue indefinitely as long as there is water. My prediction for this lab is the solution of the water is hypertonic meaning there is a higher concentration of solutes outside of the cell. To test my prediction my lab partners conducted the Brownian movement.
Bon Ami scouring powder, carmine red and Indian ink
Microscope slides and cover slip
Dropper bottles with distilled water
First we placed a small portion of Carmine red/ Indian ink onto a microscope. Then we added 3 drops of distilled water and put on a coverslip. Next we placed the slide on the microscope slide and then we observed the movement of tiny particles under 100x. We then put a lamp near the microscope to heat up the solution. Lastly, we observed and recorded results.
The particles moved in slow motion. When we put a lamp to heat up the light source there was no effects. We could see slow water molecules move. There is a continuous movement of slow particles.
Based on the results of the experiment we concluded that the solution is hypertonic. The solution is hypertonic because it has more water than ink in the cell. There are less ink molecules outside of the cell. We can see slow molecules moving inside the solution. There is little water bubbles inside and outside the cell. When we added the heat source there was no movement because there is a lot of water and not enough in particles for the cell to move. Since I did not get a chance to perform this lab, if I had the opportunity I would like to do the lab and see the results on my own. Conclusion: My hypothesis was supported. The solution was indeed hypertonic because it has more water than ink. Work Cited
Macfoy, Cyrus. General Biology: Bi 101 Laboratory Manual. S.l.: Kendall Hunt, 2012. Print.
Diffusion in Liquids
When you walk by the perfume stand in the mall you can surely smell all of the different scents celebrities are selling this day from across the room. This is an example of diffusion. It is the movement of molecules from area of higher chemical potential to areas of lower chemical potential. During this process molecules pass through and intermingle with others. In this experiment we observed the diffusion of two liquids through a colloid. My prediction for this experiment is that when the two solutions meet it will form a color to show that diffusion occurred.
Petri dish containing 2% agar
Dropper bottle with a dilute aqueous solution of potassium ferricyanide Dropper bottle with a dilute aqueous solution of ferrous sulfate
First we obtained a petri dish with 2% agar 5mm deep. We then used a cork borer to cut two holes in the agar 1cm apart. We then filled one hole with potassium ferricyanide. Next we filled the other hole with ferrous sulfate. We then observed the petri at an interval of 15 minutes. We observed and recorded results. Results:
1. Yellow solution is spreading out from the hole and into the gel and clear solution. 2. The clear ferrous was not clear to see, but it conjoined with the yellow solution 3. The blue color has formed
4. Potassium solution has formed to the ferrous solution
As shown in the results the potassium solution spread out from the hole and into the ferrous solution. When they conjoined it formed a blue solution. This showed that diffusion occurred because it moved from a high concentration to a lower one. In this case the potassium had a higher concentration so it moved toward the ferrous solution. It would be pretty awesome to do this...
Cited: Macfoy, Cyrus. General Biology: Bi 101 Laboratory Manual. S.l.: Kendall Hunt, 2012. Print.
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