Science 8th grade
Activity: Calculating Density and Error Analysis
Benchmark SC.8.P.8.3 Explore and describe the
densities of various materials through measurement
of their masses and volumes.
Objective of the Activity:
The goal of this activity is to teach students to think
critically about their methods and results, helping
them develop problem-solving skills and scientific
understanding. practicing calculating density using
the formula: Density = mass / volume
They will also reflect on common mistakes in
mathematical calculations and how these errors can
impact results. The activity reinforces mathematical
skills, critical thinking, and understanding of a
fundamental physical property: density.
Instructions:
1. Review the data provided in the tables for the
different materials.
2. Use a calculator to calculate the density of each
material. Show the division process on the worksheet
provided.
3. Answer the error analysis questions by choosing the
correct option from the four possible answers.
Table 1: Calculate Density
Material
Wood
Plastic
Mass
(g)
500
250
Volume
(cm³)
625
500
Metal
1,200
150
Error Analysis Question: If you accidentally divide the
volume by the mass instead of the mass by the volume,
how would the result change?
a. The value would be correct but in a different order.
b. The resulting value would be lower than expected.
c. The result would be completely incorrect.
d. It wouldn’t change at all.
Instructions:
1. Review the data provided in the tables for the
different materials.
2. Use a calculator to calculate the density of each
material.
3. Answer the error analysis questions by choosing the
correct option from the four possible answers.
Table 2: Calculate Density
Material
Stone
Brick
Glass
Mass Volume
(kg)
(mL)
2.5
1,000
3.0
1,500
1.8
900
Error Analysis Question: What impact would an error in
entering the numbers into the calculator (e.g., typing 1.5
instead of 1.05) have?
a. You might get a result higher than expected.
b. You might get a result lower than expected.
c. The calculation wouldn’t be affected because the
formula remains valid.
d. You might get a correct result without realizing the error.
Instructions:
1. Review the data provided in the tables for the
different materials.
2. Use a calculator to calculate the density of each
material.
3. Answer the error analysis questions by choosing the
correct option from the four possible answers.
Table 3: Calculate Density
Material
Mass Volume
(g)
(mL)
Foam
50
Cork
20
Ice
90
250
100
100
Error Analysis Question: If you round intermediate
values too much while using the calculator, how would this
affect the precision of the final density result?
a. It wouldn’t impact the result.
b. The result would be more precise.
c. The result could be less precise.
d. The result would always be greater than the real value.
Instructions:
1. Review the data provided in the tables for the
different materials.
2. Use a calculator to calculate the density of each
material.
3. Answer the error analysis questions by choosing
the correct option from the four possible answers.
Table 4:
Material
Rubber
Coal
Pumice Stone
Mass (g) Volume (cm³)
300
200
500
400
60
150
Error Analysis Question: If you forgot to convert the
units before calculating density, what kind of error could
occur in your result?
a. You would get a correct value regardless of the units.
b. Your density value might be unrealistic or incorrect.
c. There would be no impact on the calculation.
d. Units don’t matter when calculating density.
Instructions:
1. Review the data provided in the tables for the
different materials.
2. Use a calculator to calculate the density of each
material.
3. Answer the error analysis questions by choosing the
correct option from the four possible answers.
Table 5: Calculate Density
Material Mass
(kg)
Metal
Ceramic
Wood
0.8
1.2
0.5
Volume
(cm³)
100
1,000
700
Error Analysis Question: If you input the formula
incorrectly into the calculator (e.g., mass x volume instead
of mass ÷ volume), how would this affect your answer?
a. The density would be higher than expected.
b. The density would be lower than expected.
c. The calculation wouldn’t be affected at all.
d. You would get a result that makes no sense.
Instructions:
1. Review the data provided in the tables for the
different materials.
2. Use a calculator to calculate the density of each
material.
3. Answer the error analysis questions by choosing the
correct option from the four possible answers.
Table 6: Calculate Density
Material Mass
(g)
Water
Oil
Alcohol
Volume
(mL)
1,000
1,000
920
1,000
780
1,000
Error Analysis Question: If you make a mistake copying
the data from the table into your calculations, how could
you detect and correct it?
a. By comparing your results with classmates or known
sources.
b. By checking if the calculated density makes logical
sense.
c. By repeating the calculation using the original data.
d. All the above.
Instructions:
1. Review the data provided in the tables for the
different materials.
2. Use a calculator to calculate the density of each
material.
3. Answer the error analysis questions by choosing the
correct option from the four possible answers.
Table 7: Calculate Density
Material
Mass Volume
(kg)
(L)
Sand
1.5
Stone
Lead
3.2
4.0
0.75
0.8
0.4
Error Analysis Question: If you get a density that seems
unrealistically high or low, what steps could you take to
check for mistakes in using the calculator?
a. Check if the units used were consistent.
b. Repeat the calculation to confirm the result.
c. Verify that the formula was used correctly.
d. All the above.
Instructions:
1. Review the data provided in the tables for the
different materials.
2. Use a calculator to calculate the density of each
material.
3. Answer the error analysis questions by choosing the
correct option from the four possible answers.
Table 8: Calculate Density
Material
Mass Volume
(g)
(cm³)
Plastic
600
Glass
Cork
1,500
80
1,200
750
400
Error Analysis Question: If you get a very different result
for similar materials, like plastic and cork, how could you
investigate whether there was an error in your
calculations?
a. Check the original values in the table.
b. Ask a peer if they got a similar result.
c. Compare the calculated density with known or
reasonable values.
d. All the above.
Instructions:
1. Review the data provided in the tables for the
different materials.
2. Use a calculator to calculate the density of each
material.
3. Answer the error analysis questions by choosing the
correct option from the four possible answers.
Table 9: Calculate Density
Material
Mass Volume
(kg)
(mL)
Gold
19.3
Silver
10.5
1,000
1,000
Material
Copper
Mass Volume
(kg)
(mL)
9.0
1,000
Error Analysis Question: How important is it to ensure
that the units are consistent (e.g., mass in grams and
volume in cm³) before using the calculator?
a. Very important, because inconsistent units produce
incorrect values.
b. Not important since the formula remains valid.
c. It only matters if the result needs to be very precise.
d. Units don’t affect density calculations.
Instructions:
1. Review the data provided in the tables for the
different materials.
2. Use a calculator to calculate the density of each
material.
3. Answer the error analysis questions by choosing the
correct option from the four possible answers.
Table 10: Calculate Density
Material
Sponge
Foam
Rubber
Solidified
Lava
Mass
(g)
15
Volume
(cm³)
300
40
400
120
600
Error Analysis Question: If you input decimal numbers
incorrectly (e.g., 0.05 instead of 0.5), how could you
identify and correct this error?
a. By comparing your result with expected or reasonable
values.
b. By checking the original data in the table.
c. By verifying each step of your calculation.
d. All the above.
Students will play the teacher role scoring their shoulder partners worksheets
and providing feedback.
Evaluation Rubric
Instructions for Use:
1. Understand the Criteria: Familiarize yourself with the three evaluation criteria: Accuracy of
Calculations, Density with Correct Units, and Process Shown.
2. Observe and Assess: During or after the activity, check:
o
If calculations are accurate and follow the correct formula.
o
Whether density values are written with proper units, like g/cm³ or g/mL.
o
If the steps of the calculations are clearly shown and logically organized.
3. Record the Scores: Use the table below to assign a score of "Excellent" or "Needs
Improvement" for each criterion.
4. Provide Feedback: Offer specific, constructive feedback based on the scores to help students
improve.