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In the first part of the lab, we observed the movement of a drop of dye within a beaker of water. The first beaker of water was at room temperature and the dye slowly expanded and moved through the water of, seemingly, its own accord. The second beaker of water was heated (to an unspecified heat) and a similar drop of dye was introduced. The dye expanded at a quicker rate through the heated water than it had through the water at room temp. A beaker of cold water (also of unspecified temperature) received a drop of dye and the dye moved very slowly through the water. (Actually, it still hasn't completely expanded through the beaker at the time that we're writing this, approximately 20 minutes after the dye was introduced).

It can be inferred from our observations that:

a) molecules are always moving randomly (hence the expansion of dye in otherwise "still" water)

b) the higher the heat of a substance, the quicker the random movement of molecules; the lower the heat, the slower the movement; therefore, the movement of molecules is directly related to temperature

In the second part of the lab, we were asked to observe "boats" in water, that is, the movement of small plastic beads (2 microns, 4 microns, and 8 microns) in relation to the movement of the water they rested in.

We observed three different sizes of plastic beads:

2 microns: these beads moved the most, moving 13 microns in 60 seconds.

4 microns: these beads move at a moderate rate, less than the 2 micron beads, moving 10.4 microns in 60 seconds.

8 microns: these beads moved the least at 2.6 microns in 60 seconds.

The beads moved in a jittery, random pattern, (they did not move in a directed path).

We developed a new hypothesis from these obervations: the smaller the bead, the more they were affected by the movement of the water molecules.

Water molecules are definately in constant, random motion-- that much is evident from the behavior of the plastic beads.