Lab 1.2 Change
Measuring Matter        Lesson 1.2

Make Sense of Density
How to Use a Triple Beam Balance
Measuring Volume
Problem
  • Does the density of a material vary with volume?
 Skills Focus
  • Drawing conclusions
  • Measuring
  • Controlling variables
 Materials
  • balance
  • water
  • paper towels
  • metric ruler
  • graduated cylinder, 100-mL
  • wooden stick, about 6 cm long
  • ball of modelling clay, about 5 cm wide
  • crayon with paper removed
 Procedure
  1. Use a balance to find the mass of the wooden stick. Record the mass in a data table.
  2. Add enough water to a graduated cylinder so that the stick can be completely submerged. Measure the new volume of water.
  3. Place the stick in a graduated cylinder. Measure the new volume of water.
  4. The volume of the stick is the difference between the water levels in Steps 2 and 3. Calculate this volume and record it.
  5. The density of the stick equals its mass divided by its volume. Calculate and record its density.
  6. Thoroughly dry the stick with a paper towel. Then carefully break the stick into two pieces. Repeat Steps 1 through 5 with each of the two pieces.
  7. Repeat Steps 1 through 6 using the clay rolled into a rope.
  8. Repeat using the crayon.
 
Data Table

  Analyze and Conclude
Write your answers on a sperate piece of paper.
  1. Measuring For each object you tested, compare the density of the whole object with the densities of the pieces of the object.
  2. Draw Conclusions Use your results to explain how density can be used to identify a substance.
  3. Controlling Variables Why did you dry the object in Step 6?
  4. Communicating Write a paragraph explaining how you would change the procedure to obtain more data. Tell how having more data would affect your answers to Questions 1 and 2 above.
 Design an Experiment
  • Design an experiment you could use to determine the density of olive oil.
  • With your teacher's permission, carry out your plan.