Lab Activity: Graphing

Goal: Determine the relationship between the density of a material and its volume.

Type of Activity: Structured Inquiry

Materials Needed: Simulation (click on the image to open the simulation)

Activity:
1. Open the simulation and set the mass of the object to its maximum level.
2. Drag the red block onto the scale and measure and record its mass.
3. Record the water volume in the beaker.
4. Move the red block into the water beaker noting the increase in volume reading. The change in the volume reading is the volume of the red block. Record the volume in the data table for trial 1.
4. Slowly adjust the fluid density slider until the red block begins to float. Fine tune the fluid density so that the top of the block is level with the surface of the water. In this condition, the fluid density and the density of the block will be equal. Record the density in the data table for trial 1.
5. Slide the volume control a little to the right. The block will float higher in the water. Use the fluid density slider so that the top of the block is once again level with the surface of the water. Record the new density in the data table for trial 2.
6. Recalculate the new volume of the block as the difference between the original volume of the water from step 3 and the current volume reading. Record this in the data table for trial 2.
7. Repeat step 5 and 6 for trials 3, 4, and 5.
6. Create a graph of Density vs. Volume. You can create the graph by hand or use a computer application. What type of relationship is apparent from the graph? Record you answer.
7. For each trial calculate the value of 1/Density (the inverse of the density.) For example, if the density is 5 g/mL, the inverse is 0.2 mL/g. Record your calculations in the data table.
8. Create a second graph that shows 1/Density vs. Volume. Again, you can create the graph by hand or use a computer application. Draw a best fit line through the data. Use the techniques discussed in the previous presentation to find the equation of the best fit line. 
9. Compare the slope of your best fit line to the mass of the object found in step 2. 

Data Table