Density Bottle- Juliana

                     

The density bottle is a mysterious bottle that contains liquids of different densities and white and blue beads. When you shake the bottle, everything in the bottle gets mixed up and there are no clear layers. Once the bottle has been at rest for a few seconds, you can see the different layers separate. The blue beads go to the bottom of the bottle, the white beads go to the top, and the liquids remain mixed in the middle. When the bottle has had about a minute to rest, the blue beads move up and the white beads move down until they have met in the middle.

The mystery of the bottle is that because the liquid in the bottle is clear, it appears to all be the same liquid. So when someone first looks at the bottle, they are puzzled by the clumping of the beads in the center of the bottle, as well as the separation of the blue and white beads. This mystery provides an opportunity for observers to question whether the liquid really is water, or if it is something else. And when you look very closely at the liquid, you can see that the liquid that floats to the top of the bottle does actually have some very tiny particles in it that make it clear that it is not water, while the clearer liquid on the bottom most likely is water.

While playing with the density bottle on Tuesday, someone mentioned that the density bottle reminded them of salad dressing, because when you leave salad dressing to sit for a while, the different parts separate, which was similar to what happened with the density bottle. Another connection that was made in class was how the density bottle was similar to a Venn diagram when the beads are separated on the top and the bottom, with the pure liquids below the blue beads and above the white beads. Making connections to outside experiences is an important part of scientific discovery. Asking what outside connections can be made to exhibits is a great way to engage visitors because it encourages them to be creative and think outside the box.

Another idea that came up in class was how normally when you have liquids of different densities in one container, you can see a distinct line between the liquids when they are separated. For example, when you have water and oil in a container, you can clearly see where the oil is sitting on top of the water. In the density bottle, however, this line is not as clear because the beads are covering up this line. It may be interesting to have a second bottle that also has these two different liquids, but without the beads so that this separation may be clearer to observers.