Name ______________________________________________
Assignment # ___________
MASS, VOLUME, AND DENSITY
INTRODUCTION
An old riddle asks “Which is heavier, a pound of feathers or a pound of lead?” The question is
nonsensical, of course, since a pound of feathers and a pound of lead both weigh the same,
one pound. Nevertheless, there is clearly something different about a small lead brick and a
large bag of feathers, even though they weigh the same. The key to answering the riddle is
undrstanding the relationship that exists between a substance’s mass and the volume it
occupies. This relationship is expressed by the physical property called density. The density of a
substance, unlike its mass or volume, is characteristic of the nature of the substance. A
substance like gold will have a particular density, different from that of iron, or water, or lead.
Density is defined as the ratio of a substance’s mass to the volume it occupies.
Density 
Mass (g)
Volume (mL)
PURPOSE
In this experiment you will accomplish the following:
1. Determine the density of several liquids and solids.
2. Identify an unknown metal sample by its density.
3. Calculate the percent error within the class for a specific sample.
PROCEDURE
You are responsible for creating your own data tables for this lab. Don’t forget to use units!
A. Finding the density of liquids.
1. Determine the mass of a clean, dry, empty 25-mL graduated cylinder using the balance.
2. Pour 10mL of water into the cylinder (make sure you’re looking at the bottom of the
meniscus when measuring).
3. Measure the mass of the cylinder and water.
4. Calculate the mass of water.
5. Using the equation above, calculate the density of water.
6. Repeat steps 1-5 for samples of unknown liquids A and B
B. Identifying an unknown metal by determining its density.
1. Select one unknown metal sample to investigate. Observe the color of the rod.
2. Determine the mass of the unknown to the nearest 0.01grams using a balance.
3. Find the volume of the metal sample by water displacement:
a. Fill a 25mL graduated cylinder about half-full with water, measure and record the
volume as accurately as possible.
b. Carefully release the metal sample into the graduated cylinder so it is completely
submerged in the water.
c. The amount of water displaced is equal to the volume of the solid.
TABLE 1
4. Using the formula shown above, calculate the density of your unknown.
Metal Density
5. Identify your metal sample using Table 1.
Aluminum 2.78g/cm3
Copper 8.8 g/cm3
Carbon Steel 7.79 g/cm3
Brass 8.31 g/cm3
Name ______________________________________________
Assignment # ___________
C. Calculating percent error.
1. Obtain three chocolate M&M’s for your group (Do not eat them!))
2. Determine the mass of the M&M’s using a balance.
3. Using the water displacement method determine the volume of the M&M’s.
4. Calculate the density of an M&M.
5. Write the density that you obtain on lab whiteboard.
6. Once all groups have recorded their results, we will calculate the percent error as a
class.
Percent error = |accepted value – experimental value| x 100%
accepted value
ANALYSIS QUESTIONS (ON A SEPARATE SHEET TYPED)
1. The density of water is 1.00 g/mL. How accurate was your calculation in Part A? What
are some possible sources of error that could have occurred to result in an incorrect
density value? (2 pts)
2. Using your density results for water, liquid A, and liquid B; sketch a picture of what it
would look like if you poured all three liquids into a large graduated cylinder. (3 pts)
3. Using the accepted value for the density of a metal (as shown in Table 1), calculate the
percent error of your calculated metal density in Part B. (2 pts)
4. Do you think that determining the volumes of your metal samples by measuring their
dimensions and calculating would be more or less accurate than determining these
volumes by water displacement? Explain. (2 pts)
5. Were the class results for the density of an M&M precise, accurate or both? Explain.
(Refer to Chapter 3 if you need help with these terms.) (2 pts)
6. Would the water displacement method work for calculating the density of a tablespoon of
salt? Explain. (2 pts)
LAB REPORT
-Submit a data table that contains all of your mass, volume and density calculations for water,
liquid A and B, the metal cylinder, and M&M’s. The table must be an electronic table! (7 pts)
-On a separate sheet of paper, please type the answers to all of the analysis questions. Leave
space for question 2 and feel free to draw your answer freehand.
-At the top of both sheets, include your name, period, and a title for your lab. I don’t mind
catchy titles.