Name:_______________________
Period:_________________
Density Simulation
Pre-lab Questions:
1. What is mass?
2. What is volume?
3. What equation do we use to calculate density?
4. In your own words give a definition of density.
Go to the PhET simulation of density by typing in this web address:
http://phet.colorado.edu/sims/density-and-buoyancy/density_en.html
or Google Search PhET, choose Chemistry simulations, choose density, click Run Now
Activity 1
On the first screen you have two options, you can choose “my block” or you can choose “material”, start off
with “material”. In the drop down menu you can change the material that the block in the water is made of.
There is a scale that tells you the density of the material.
1. Which of the materials float in the water and which of them sink?
2. Compare the densities of the items that float to the items that sink; what is the difference?
3. There are two sliders, one for mass and the other for volume, what happens to the other slider when
you move one of the sliders? Why does that happen?
Activity 2
Now change to “my block”, find a mass and volume that gets the top of the block even with the surface of the
water (not sticking up out of the water and not sinking to the bottom)
4. What mass and volume did you choose?
5. What is the density of your block?
6. Explain why that works?
Activity 3
On the right hand side of the screen change the setting from “Custom” to “Same Mass”. There are four blocks
that appear red(the smallest), green, blue, and yellow (the largest). You can move each of these blocks in an
out of the water.
7. List the order of the blocks from smallest density to largest density. Use what you know about the
mass/volume relationship to do this.
8. Describe the pattern of volume?
Activity 4
Now on the right hand side change the setting to “Same Volume”, this time all of the blocks are the same size
but they have different masses. You again can move the boxes in and out of the water.
9. List the order of the blocks from smallest to largest density.
10. Describe the pattern of mass?
Activity 5
Now on the right hand side change the setting to “Same Density”.
11. Describe the pattern with the blocks mass/volume relationship to give the blocks the same density?
12. Which of the block sink and which float? Explain why this happens?
Activity 6
Lastly, you will change the setting on the right hand side to “Mystery”. In this section you are able to obtain
the mass of each block by putting it on the scale and can place the blocks in the water. Your job is to identify
the material that each block is made out of based on the density you find and the table provided. You can see
the table by clicking on the “Show Table” tab on the right hand side of the screen. Fill in the chart below.
*Note: A block must be completely under water in order to get its correct volume. You can use the mouse to
hold it under the water.
Block
A
B
C
D
E
Mass (kg)
Volume (L)
Density (kg/L)
Material