Oblek Laboratory

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Is it a colloid?
suspension?
Or could it be a solution?
Mrs. Wade
Directions: Before beginning this laboratory exercise the class will read the
directions together and then each lab pair will again rewrite the steps and show them to
me before proceeding to the back tables to begin the experiment. You must do the steps
in order and write the observations and answers on the answer sheet as you go along.
This means that you must have the answer to step one written on the answer sheet before
proceeding to step two. If you cannot control your urges to put ooblek onto another
person or on yourself, you will be asked to sit down or leave the classroom and will be
given a zero for this laboratory exercise. The same rules apply to fooling around during
the lab.
1. After writing down the steps, go back to the lab table (with your partner) and wait
patiently for the rest of the class to begin.
2. The instructor will give each student his or her own sample of ooblek to test. Hold
the sample in the cup DO NOT TOUCH YET!!!. A) What color is the sample? B)
What does it look like? C) What is its consistency?
3. QUICK FINGER POKE TEST: Take your index finger and quickly poke through
till you touch the bottom of the cup then pull it out quickly. This should not take you
over 1 second to do. A) Were you able to poke through the substance? B) Did the
oblek conform around your finger? C) What did the substance feel like?
4. SLOW FINGER POKE TEST: This time take your index finger and slowly poke
through the ooblek, until you feel the bottom of the cup. Then slowly bring your
finger out from the ooblek. A) What was different this time as compared to step 3?
5. CONFORMITY TEST: Make a cup shape with the palm of your hand. Then slowly
pour some of the ooblek into your palm. Return your ooblek to the cup. A) Does the
oblek conform (shape to) your palm? B) Did it conform quickly or slowly?
6. POUR TEST: Take the ooblek from the cup then pour it into another cup. While
you are pouring look at the clock or your watch and time how long it takes to pour
into another cup. A) Does the ooblek pour? B) How much of it poured into the other
cup? C) How long did it take?
7. BOUNCE TEST: Pour some of the ooblek into the palm your hand. Shape it into a
ball and then bounce it on the LAB TABLE. A) What did the ooblek do?
8. SHATTER TEST: Use the ooblek that you already have in your hand from test 7.
Set the oblek down on the lab table and take a spoon, and strike the oblek. Be sure
not to hit it directly with a flat surface because it will cause the ooblek to splatter and
fly all over the place. A) Did the ooblek break? B) What did happen to it?
9. SHAPE TEST: Pour some of the ooblek into the palm of your hand and form it into
a ball. Try to have the oblek form a ball for 5 seconds. A) Did the ooblek hold its
shape for five seconds? B) If not, how long did it hold shape for?
10. What is this substance and why is it that?
11. What are the three types of mixtures found in this living material?
Suspension, solution or colloid
a.
b.
c.
intracellular fluid:
whole blood
blood plasma
12. When you are finished please clean up ALL OOBLEK from your table and chair. If
there is ooblek on the floor be sure to wipe that up as well. The ooblek cleans up
easily with either water or cleaning spray. Be sure to throw your cups in the trash and
wipe your table and chair down one more time after it’s had time to dry (it leaves a
residue).
ANSWER SHEET TO OOBLEK LAB
2A.
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2B.
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2C.
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3A.
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3B.
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3C.
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4A.
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5A.
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5B.
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6A.
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6B.
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6C.
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7A.
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8A.
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8B.
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9A.
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9B.
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10.
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11A.
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11B.
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11C.
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