Metric - Volume Lab KEY

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Name: _________________________________Date_________________ Period_________
The Metric System: LAB ACTIVITY
Metric Measurement: VOLUME
Introduction: The volume of a cube can be calculated by multiplying its length times its width
times its height. How could you figure out the volume of a rock that has broken and chipped
edges? How could you figure out the volume of a bag of marbles without doing a lot of math?
Objective: In this activity, we will learn how to read the volume of a liquid in a graduated
cylinder in millimeters (ml) by reading the meniscus of the liquid (see diagram below). When
most liquids are placed in tall, narrow containers, they tend to creep up the walls of the container
due to capillary action. This results in the surface of the liquid appearing to be curved. The
bottom of this curve is known as the MENISCUS. In this activity, we will also learn how to
measure the volume of oddly-shaped objects.
Practice: Measure the volume of the liquid
in the graduated cylinder. Record below.
___36.5____ ml
Procedure:
1. Record the names of the four objects in the table on the following page
2. Pour the liquid from your beaker at your lab station into the graduated cylinder. Make
sure the level of the liquid is bewtween 50 ml and 70 ml.
3. Ensure that you are at eye level with the level of water in the graduated cylinder. Read
and record the number of millileters (to the nearest tenth of a ml). Record this volume
and in the “Beginning Volume” column for the first object.
4. Gently lower the first object into the liquid. Read the new volume and record in the
“Volume of Liquid and Object” column for the first object. (The amount the water rises is
equal to the volume of the object)
5. Calculate the volume of the object alone by subtracting the “Beginning Volume” from
the “Volume of Liquid and Object”. Record answer in the “Volume of Object” column
for the first object.
6. Repeat steps 3 through 5 for the remaining three objects. (HINT: There is a shortcut that
will allow your group to complete the data collection more quickly! See if your group can
figuure out the shortcut.)
OBJECT
Nail
(Head Down)
SAMPLE DATA
VOLUME OF LIQUID BEGINNING VOLUME
AND OBJECT
(Liquid Only)
VOLUME OF
OBJECT
61.3 ml
60.0 ml
1.3 ml
Die
64.8 ml
61.3 ml
3.5 ml
Marbles
69.0 ml
64.8 ml
4.2 ml
Pennies
70.1
69.0 ml
1.1 ml
Questions:
1. Did your group figure out the shortcut?
You can use the final volume (Volume of Liquid and Object)
asthe beginning volume of for the next object.
2. If so explain how the shortcut allowed your group to complete
the activity more quickly.
You did not have to pour the water out each time and
record a new starting volume for each object.
3. What kind of error would result if you read the liquid volume
where the liquid touches the wall of the cylinder rather than
the meniscus?
The volume you would meausre would be higher each time.
(NOTE: If you were measuring out a specific amount of water
for an experiment, this would cause the volume to be too high
but how would it really affect the results of this lab?)
4. How does the “measuring volume by difference” method compare
with measuring volume using math for these odd-shaped objects?
Explain which method would be easier.
It is much easier to determine the voulme using “volume by
Difference” because you do no have to measure many
different lengths and try to calculate the voulme, you just have
to measure how much the water went up after the object was
placed in the water.
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