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In discussing the idea of movement and diffusion, Paoli and I (Laura) predicted that substances diffuse faster depending on their movement. We believe that increased energy causes increased movement and in turn allows for a faster diffusion process. Also, we think that the smaller the particles the less energy will be needed for maximum movement. Therefore our prediction is that the best conditions for maximum diffusion are small particles and a lot of energy.

When looking at the micron balls, we discovered our hypothesis to be true! The 2 micron balls moved the fastest then followed the 4 microns and lastly the 8 micron balls.

Our Data:

all observed at 40x under microscope

2 micron balls - move somewhat fast, there is shifting within the liquid, wiggle in place and then in a circular motion

4 micron balls - clumpy, moving somewhat faster than 2 micron however hard to REALLY tell

8 micron balls - very separated, moving extremely slowly.

THE ONIONNNNNNNNNNNNNN:

At the beginning of this experiment both Paoli and I we very discouraged and frustrated: WE COULDN'T SEE ANYTHING BESIDES CELLS!!! However, once Will put the slide on the projector, we started to notice the cells reacting to the water and the sodium chloride mixture. We observed that by adding water to the slide, the onion cell's sac absorbed the water and expanded. When we added the the NaCl solution to the onion slide, we noticed the cell's sac "dried" up and looked crinkled.

We know that when NaCl is diffused in water it "breaks" apart into positive Na ions and negative Cl ions. We decided that ions don't exist long by themselves due to their charge. The charge makes them "attractive" and "attracted" to other atoms and molecules. H2O is the only other atom in the solution, so we decided that the ions start a type of bond or some such thing to "absorb" the water molecules making them no longer just H2O. We think that the ions actually take the water molecules from the cells, essentially "burning" them and making them "crinkled". Although this was witnessed in regards to the cell's sac, we didn't notice an effect on the cell's wall.