answer key

Density Dilemma This is just a sample key. Answers may vary greatly.
You have been given 3 pieces of raw potato. Your job is to find a way to
make 1 piece sink, 1 piece float, and 1 piece stay suspended in water.
Discuss the dilemma with your group and come up with a procedure
that will enable you to solve the problem. Your procedure must be
approved before you may begin.
Mass
Volume
Potato 1
Density
1.3g/ml
Potato 2
1.3g/ml
Potato 3
1.3g/ml
Water 1
Change?
Add 3T salt
Mass
Volume
Density
1.5g/ml
Water 2
No change
1.0g/ml
Water 3
Add 3t salt
1.3g/ml
Claim: (This is your conclusion) Ex- If density of object > density of
liquid, then object will sink. If density of object < density of liquid, then
object will float. If density of object = density of liquid, then object will
be suspended in the liquid.
Evidence: (Pull specific data from your experiment that proves your
claim) Ex- All potatoes had the same density, which was 1.3 g/ml.
Water 1’s density was 1.5 g/ml, which was more than the potato. Water
2’s density was 1.0 g/ml, which was less than the potato. Water 3’s
density was 1.3 g/ml, which was the same as the potato.
Reasoning: (What scientific knowledge can you apply that supports
your claim) Ex- To find density, we use the formula D = m/v. As we
apply the formula, we see that objects with higher densities always
place themselves lower than things with lower densities.
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