Objective or Purpose:

To explain observations using the concept of atoms

 

Hypothesis:

When vegetable oil, water and syrup are poured into the glass, the oil will be on top, the water in the middle and the syrup on the bottom.  The rock will sink to the bottom, the grape will float on the syrup, the ice cube will float on the water, and the cork will float on the oil.

 

Materials:

Vegetable oil

Water

Maple or corn syrup

A grape

A piece of cork

An ice cube

A small rock

A tall glass

Eye protection

 

Procedure:

Equal amounts of vegetable oil, water and maple syrup were poured into the glass.  Next the rock was dropped into the glass, then the grape, then the ice cube and then the piece of cork.

 

Data:

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

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

 

Results:

The liquids did not mix. Instead they formed layers in the glass with the syrup on the bottom, the water in the middle, and vegetable oil on the top.  The rock sank all 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.

 

Discussion and Conclusions:

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 the 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.