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Kerlyne Jean

Kyree Harmon

Based on our class discussion, we hypothesize that since water molecules are moving, small beads will jitter more than large beads. We observed 3 different sizes of spheres and 2 spheres within each size. For the 2 micron spheres, we observed movement in both, one for 28.6 microns and the other for 65 microns with an average distance of 31.2 microns. For the 4 micron spheres, we measure movement in only one sphere which was approximately 2.6 microns while the other sphere jittered without any forward or backward movement. In the 8 micron spheres we still observed 2 spheres but measured no movement for each.

The findings from our observations support our hypothesis. Because water molecules are moving and creating approximately the same force on each side of the spheres, the larger spheres did not appear to move as the forces cancel each other out. However, with the smaller spheres, smaller surface creates more chance for uneven force on each side, thus causing difference in force and visible movement.

Part 2

We continued this experiment with an observation of onion cells. When we added NaCl to the cells, the random movement of molecules was obviously stronger on one side than the other, pushing the cell membrane away from the cell wall and into the cytoplasm of the cell. Based on these observations, we wonder whether the random movements of the NaCl molecules are faster than those of water, which would cause the ueven movement of the cell membrane or a stronger force on just one side. We also question whether or not the size of the cell affects the speed of the molecules that affect it and whether or not the moving molecules "bump" the cell walls. Lastly, we wonder how whether other molecules of other chemicals move also and how.