Oobleck Lab!
( Warning!! This lab has the potential to get very messy. Do not do anything that is inappropriate for a lab. If you choose to do so, you choose to get a zero on this lab)
Background on Non-Newtonian Fluids and Colloids
Many of the materials we use every day, like starch, are made up of molecules called POLYMERS. POLY means many and MER means unit. Because the units in chains are so long, they interfere with the ability of the solution to flow. Viscosity is a physical property of liquids that describes how they flow.
Honey and corn syrup are described as having high viscosity because they flow more slowly than water.
In this lab, it will be useful to know the different types of mixtures. Solutions and colloids are mixtures that are uniform throughout the mixture. A suspension, on the other hand, is a type of mixture that is unevenly distributed throughout the mixture. Usually suspensions are opaque or "smoky" looking and do not transmit light. A good example would be really fine sand in water. Keep these facts in mind while you are observing your Oobleck creation.
I. Problem: Which state of matter is Oobleck? Solid, liquid, gas??
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II. Hypothesis: If we mix cornstarch water, then its state of matter will be a
III. Justification Statement: Write at least two sentences to explain why you made the hypothesis that you did. This typically described as If, then, and because. Use scientific vocabulary in your answer and do not state that it's because that's what the notes say.
Materials250 ml beaker / 50mL graduated cylinder
l 75mL cornstarch
I OOmL water
1 plastic cup
Paper plate
scupula
IV. Procedure
1. Draw the data table below.
2. Measure out l 75mL cornstarch into the 250ml beaker.(just estimate using the readings on the side of the 250mL beaker) .
3. Pour this into the paper cup.
4. Measure out 1OOmL of water. Add a small amount of water at a time to the cornstarch until the mixture begins to thicken (somewhat like the consistency of yogurt) . Stir carefully! Don't fight the viscosity of the Oobleck! !!
5. Thin k about the following things, because you will enter the behavior of Oobleck into your data table: Try to cut the Oobleck with the scupu la. Slap the top of the Oobleck in the paper bowl. Pour some Oobleck into your hands and roll it into a ball. Does the ball keep its shape? Make an Oobleck snake and pull it apart quick ly. What happens? Draw in the Oobleck with your scupula. Write your name in it.
6. Fill in the data table after you have cleaned up.
V. Results: Write down at least one sentence per "What Happened? "
What Did I Do? / What Happened? / Behaved Like Which State of Matter?Try to cut Oobleck
Slap the top of Oobleck in the bowl
Pour some Oobleck into your hands and roll it into a ball
Make an Oobleck snake and pull it apart quickly
Draw in the Oobleck with your scupula
(Fill in your own experiment)
(Fill in your own experiment)
Note : Make sure that you have discussed with your group, 2 new things you could do to the Oobleck to learn more about its properties.
VII. Conclusion Questions
1. How does the viscosity change with force?
2. Define suspension, solution and mixture in your own words and include an example of each.
3. Is Oobleck better classified as a solution or a suspension? Explain your answer.
4. When it behaves like a solid, what type of a solid would you consider it to be?
VI. Conclusion: Write the conclusion with all of your group members . This should be at least one paragraph long. Begin by stating whether or not your hypothesis was accurate (accept it or reject it). Next , answer the problem question found at the beginning of the lab. Then, explain your answer using all of the vocabulary words and phrases highlighted at the beginning of the lab.