Knowledge Base Article

Article ID: 27154 [Last Updated12/13/2001 5:39:11 PM]

Summary:
Sample General Science lab report

Article:
Experiment 1.1

Data:

After the water, syrup, and vegetable oil were added to the glass, it looked like this:

(Drawing of the glass showing the layers that formed. The layers should be labeled.)

After the rock, grape, ice cube, and cork were added, it looked like this:

(Drawing of the glass showing the layers that formed and where the rock, ice cube, grape, and cork are. The layers and the items should be labeled.)


Summary:

In this experiment, I put water, syrup, and vegetable oil into a glass. The liquids did not mix. Instead, they formed layers in the glass. The syrup was on the bottom; the water was in the middle; and the vegetable oil was on the top. Then, I dropped a rock, a grape, an ice cube, and a piece of cork into the same glass. The rock sank all of the way to the bottom. The grape floated on top of the syrup layer. The ice cube floated on top of the water layer, and the cork floated on top of the vegetable oil.

This experiment demonstrated the concept of density. Density tells us how tightly-packed the atoms of a substance are. Of the three liquids, the syrup was the most dense. This means that its atoms are so tightly-packed that they can shove their way through the atoms of the other liquids, and therefore the syrup ended up at the bottom of the glass. Since the water floated on top of the syrup, it is less dense than the syrup. Since the vegetable oil floated on the water, it is less dense than water.

When the other things were put in the glass, they ended up in a particular layer of liquid, depending on their own density. The rock fell to the bottom of the glass since it is more dense than any of the liquids. The grape ended up floating on top of the syrup layer because it is less dense than syrup but more dense than water. The ice cube floated on the water because it is less dense than water but more dense than vegetable oil. Finally, the cork floated on top of the vegetable oil because it has the lowest density of everything.