Science Performance Task
8th Grade – Physical Science
Standard(s): SC.8.P.9.1 Explore the Law of Conservation of Mass by demonstrating and concluding that mass is conserved when substances
undergo physical and chemical changes.
SC.8.P.9.2: Differentiate between physical changes and chemical changes.
Description
Students determine the difference between physical and chemical changes and their relationship to the Law of Conservation of
Mass. The major concept that students should demonstrate is that mass is conserved when substances undergo a physical or
chemical change (Law of Conservation of Mass).
Task
1. Design an experiment to determine the effect on mass when a substance undergoes a physical change.
2. Design an experiment to determine the effect on mass when a substance undergoes a chemical change.
Materials
Reaction of Alka Seltzer
Triple beam balance
1 balloon
Water
2-liter soda bottle
4 Alka Seltzer tablets
String
General Info 
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Mix It Up
Triple beam balance
Water
Food coloring
Large zip lock bag
2 Beakers
Burning of Wax
Triple beam balance
4 birthday candles
Matches
Graduated cylinder
Bottles with stoppers
Vinegar Eruptions
Triple beam balance
1 balloon
Vinegar
2-liter soda bottle
Baking Soda
String
This task is designed to take students approximately 45-50 minutes to complete.
Students will be working in pairs during this exercise.
Students should be ready to work as soon as the period begins. The materials should be set out at each lab station, if
possible. A central supply area, if needed, should be easily accessible. All supplies should be clearly labeled.
All Safety Procedures should be strictly adhered to.
Revised 9/9/2015
1
Science Performance Task
Rubric
Understanding
of Concepts
Hypothesis
Design
Communication
Poor
1
Fair
4
Good
7
Excellent
10
Mostly inaccuracies;
Poorly prepared;
significance is not
understood.
Three – four
inaccuracies or
contradictions; All
aspects of
significance are not
recognized
4
Hypothesis match
the overall question
but does not predict
the relationship and
is phrased incorrectly
One or two minor
inaccuracies or
contradictions; All aspects
of significance are not
recognized.
No inaccuracies concepts
are well understood; All
aspects of significance are
recognized.
7
Hypothesis match the
overall question and
predicts the relationship
but is phrased incorrectly
10
Hypothesis statement
match the overall question
and predicts the
relationship Hypothesis is
stated correctly
4
The procedures
match the question
and hypotheses;
procedures not clear
enough to replicate
experiment; safety
procedures are not
followed.
7
The procedures match the
question and hypotheses;
procedures are clear
enough to replicate
experiment; safety
procedures are not
followed.
10
The procedures match the
question and hypotheses;
procedures clear enough to
replicate experiment; safety
procedures followed.
4
Explanations are
clear and tied directly
to the question &
hypothesis;
Conclusions are Not
justified with
evidence and logical
reasoning; results
are not concisely
shared.
7
Explanations are clear
and tied directly to the
question & hypothesis;
Conclusions are justified
with evidence and logical
reasoning; results are not
concisely shared.
10
Explanations are clear and
tied directly to the question
& hypothesis; Conclusions
are justified with evidence
and logical reasoning;
results concisely shared.
1
Hypothesis does not
match the overall
question, does not
predict relationship
and is stated
incorrectly
1
The procedures do
not match the
question and
hypotheses;
procedures are not
clear enough to
replicate experiment;
safety procedures
are not followed.
1
Explanations are not
clear and tied directly
to the question &
hypothesis;
Conclusions are Not
justified with
evidence and logical
reasoning; results
are not concisely
shared.
Score Comments
Total Score:
Revised 9/9/2015
2