Name:______________________________________
Date: ____________ Period: ______
Gummy Bear Osmosis Lab
Purpose
To investigate osmosis (the movement of water) into and out of a polymer.
Background
Gummy bears are made of gelatin and sugar. Gelatin is a polymer that forms large three-dimensional matrices,
which give structural support to jellies and jams. The movement of water into or out of a Gummy bear is
very similar to how water enters and leaves living cells.
Molecules are always moving. Remember that DIFFUSION is the movement of molecules from an area that is
highly crowded to an area that is less crowded.
OSMOSIS is similar to DIFFUSION. OSMOSIS is the diffusion of water molecules through a selectively
permeable membrane.
Remember that selectively permeable means some molecules can move through the membrane while others
cannot.
Testable Question (4 pts)
How will soaking Gummy bears in tap water and salt water affect the mass (and overall size) of a Gummy
Bear?
__________________________________________________________________________________________
__________________________________________________________________________________________
Variables
Manipulated variable: type of liquid that Gummy bears are placed in
Responding variable: mass (and overall size) of the Gummy bears
Controlled variables (4+): initial size of Gummy bear, brand of Gummy bear, amount of liquid, type of cup,
environment
(6 pts)
Hypothesis: If Gummy bears are soaked in different solutions, then the Gummy bear not soaked
will…,__________________________________________________________________________________
the Gummy bear soaked in water
will…__________________________________________________________________________________
and the Gummy bears soaked in salt water will… because…
_________________________________________________________________________________________
Materials
o (3) Gummy Bears
o Salt
o (3) glass jars (16 oz)
o Paper towels
o Centimeter ruler
o spoon
o Tap water
o Label (3 pieces)
o Stopwatch
Procedure: Day 1
1. Obtain three glass jars and three gummy bears of the different color.
2. On one label, write “Bear 1,” “Control”
3. The other label should indicate “Bear 2,” “ Water”
4. The third label should indicate “Bear 3,” “ Water + Salt”
5. Put nothing into cup one “Bear 1”.
6. Measure 70 ml of tap water and pour into cup “Bear 2”.
7. Measure 70 ml of tap water and pour into cup and a lot of salt until cloudy“Bear 3” and
stir it up..
8. Place the bears in the cups.
9. Measure your bears from top to bottom (height), from side to side (width) and from front
to back (depth). Use your measurements to calculate the volume (h x w x d). Record
your data in the data table. Measure the values for each one separately, since they may
have different measurements.
10. Place the bears in the cups.
11. Place the cups on the counter on the periphery of the classroom and let them soak t.
Procedure: Day 2
12. On the next lab day, gently pour the water from each cup over a sink.
13. Catch each bear on a piece of paper towel. While on the towel, measure the height, width,
and depth. Calculate the volume. Record your data.
14. Blot the bear dry by using paper towel.
Data Table: (24 pts)
Dimensions
Height (cm)
Width (cm)
Depth (cm)
Volume (cm3)
Gummy Bear 2
(water)
Gummy Bear 3 ( water
+ Salt)
Before
Soaking
(day 1)
Before
soaking
(day 1)
After
water
(day 2)
After
water
(day 2)
Gummy
Bear
control
NO Soaking
(day 1)
NO
Soaking
(day 2)
Data Analysis
1. Calculate the percent change in volume after each step of the experiment.
% change in volume = final volume - initial volume
initial volume
Analysis
(12pts)
Bear 1
Bear 2
x 100
Bear 3
% Change in Volume
From Day 1 to 2
QUESTIONS:
1. State what effect, if any, does soaking Gummy Bearss in water or salt water have on the
size of the Candy?: (4pts)
________________________________________________________________________
________________________________________________________________________
_______________________________________________________________________
2. Describe what happened to your gummy bear after soaking it in tap water over night:
(4pts)
________________________________________________________________________
________________________________________________________________________
_______________________________________________________________________
3. Describe what happened to your gummy bear after soaking it in tap water over night:
(4pts)
________________________________________________________________________
________________________________________________________________________
_______________________________________________________________________
4. What changed the most, the height, width or mass of your tap water gummy bear? (2pts)
________________________________________________________________________
________________________________________________________________________
5. Describe what happened to your gummy bear after soaking it in salt water over night:
(4pts)
________________________________________________________________________
________________________________________________________________________
________________________________________________________________________
6. What changed the most, the height, width or mass of your salt water gummy bear? (2pts)
________________________________________________________________________
________________________________________________________________________
________________________________________________________________________
 https://www.youtube.com/watch?v=8atErlFKd2A