Bubbles Up: a Science Experiment on Density

Topics: Liquid, Water, Petroleum Pages: 10 (3744 words) Published: January 8, 2013
Bubbles Up: A Science Experiment on Density

Density is the measure of the quantity of some physical property [usually mass] per unit length, area, or volume (YourDictionary.com). How does temperature affect density? Do items become denser after being frozen? It is well known that water becomes denser when it's temperature lowers until its freezing point. Does this principle apply to oil; and if so, which kinds? This question easily applies to real world problems. For example, when there is an oil spill in the ocean, the clean up crews have to know how dense the oil is before simply cleaning it up. If the oil is dense enough that only very small amounts are rising to the surface, the clean-up team will have to come up with a deep cleaning plan that won't harm marine wildlife. On a more everyday level, understanding how certain car oils are affected by weather, thereby affecting their density, is necessary to keep one's car running adequately without leaving harmful residue behind in the mechanics.

For this experiment, I will be testing the density of three different kinds of oil: olive oil, mineral oil, and Wilbert's lemon oil. I will test the oils' density before and after being placed in the freezer to see if there is a noticeable difference in the density of the oil. I predict that all of the oils featured in this experiment will be more dense after sitting in the freezer for an hour. I came up with this hypothesis after reviewing other density related science experiments. What further assisted in the making of this hypothesis was the recalling of the fact that objects with lower temperatures (such as air or water) become denser.

Two experiments that I found to be quite similar to this one were the Density Column and the Bubbling Lava Lamp. The Density Column measures the density of seven different liquids by layering them on top of each other. By doing this experiment, one is able to find out which liquid is the most dense; with the order ascending from there. Based on the results, they found that not all oils are the same density. Vegetable oil came in fifth from the bottom of the tower; lamp oil was the seventh and last layer in the column (Spangler, 2012). In the Bubbling Lava Lamp experiment, the fact that water is denser than vegetable oil was taken advantage of. Using an Alka-Seltzer tablet, the formed carbon monoxide bubbles that pushed the water up and through the vegetable oil. What happened thereafter is that the Alka-Seltzer bubbles would pop and the colored water would sink back down to the bottom of the container through the oil (Spangler). Regardless of penetration, the two liquids did not mix. While temperature was not a key factor in either experiment, they did show that the liquids differing in densities would not mix despite what was happening to them or around them – and that is important for this experiment. In order for Bubbles Up to work properly, the oils cannot mix with the water they are floating on top of no matter what happens.

To conduct the science experiment, I used the following items:

(3) 12 ounce cups
(1) marble
(1) dime
(1) penny
a pitcher of water
a bottle of olive oil
a bottle of mineral oil
a bottle of Wilbert's lemon oil
blue food coloring
a freezer
a timer
a measuring cup
a spoon or a pair of tongs to retrieve the objects from inside the cups soap and water solution to clean the objects off
paper towel
thermometer

: In the experiment Bubbles Up, the observer will drop various objects into each of the three cups and record how many bubbles of oil they observe. While the results may vary slightly from mine, it may be because of ambient temperature of the room they are working in. This design plan was chosen because timing how fast an object fell to the bottom of the cup is impossible without computer assistance. However, counting how many bubbles of oil occur within the water is a good measure of how dense the oil is because of it being light enough...