Name: __________________________
Date: ________________ Class Period: ________________
Lab: Observing Osmosis in Gummy Bears
Problem: Where is the concentration of H20 (water) molecules
the highest; tap water, distilled water, salt water, or gummy bears?
Background
Information:
*takes notes from
the power point:
*Diffusion: the movement of
________________ from an area of ___________ concentration to an area of
_________
Concentration
*Molecules are in ___________ motion,
and tend to move from areas of higher concentrations to area of lower
concentrations.
*Selectively Permeable Membrane: some molecules can move through a ____________________
while others cannot.
Example:
____________________________
*Osmosis: the diffusion of
___________________________ through a
_________________________________,
from an area of high concentration, to an
area of lower concentration.
Gummy bears are made of gelatin,
starch and sugar.
·
Gelatin is a
polymer (huge molecules made of many repeating units), that forms a 3-D
·
structure (a
matrix) that gives structural support to jams, jellies, and many other things.
·
A matrix is like
a complex cage
Hypothesis: Circle your choices to create your hypothesis:
1.If the water concentration in tap
water is (higher, lower) than the
water concentration in a Gummy Bear, then the Gummy Bears placed in the tap
water will (increase, decrease, remain
the same) size.
2. If the water concentration in distilled water
is (higher, lower) than the water
concentration in a Gummy Bear, then the gummy bears placed in distilled water
will (increase, decrease, remain the
same) size.
Safety Considerations:
There
are no safety hazards with the materials in this lab. But you should use
caution in a lab, and when working with all lab materials.
Materials: per group
X 4
gummy bears (of different colors)
Marker
or pen
4
paper cups
Ruler
Procedure:
Day 1:
1.
Put 1 gummy bear
in each cup (there are 4), and write your name, class period, and the gummy
bear color on the cup.
2.
Label each cup:
|
Cup 1:
Tap
Water
|
Cup 2:
Tap
Water with Salt
|
Cup 3:
Distilled
Water
|
Cup 4:
Distilled
Water with Salt
|
3.
Measure each bear
(in cm), and record on the data table
*Lengthwise (from top to
bottom)
*Width (side to side)
*Height (front to back)
*Calculate the volume. (Length x width x height)
4.
Find the mass of each bear in grams,
using the mass scale.
5.
Place the bears in the cups.
6. Cup 1: place a bear, and cover completely
with tap water.
7. Cup 2: mix a small amount of salt
with tap water, and completely submerge a bear.
8. Cup 3: place a bear, and completely
cover with distilled water
9. Cup 4: mix a small amount of salt
with distilled water, and completely submerge a bear.
10. Place them on your class period’s tray, and let
them sit over night
Day 2:
1.
Gently remove
your bears from the cups, keeping them separate, and not mixing up bear 1, 2, 3
and 4.
2.
Place on a piece
of paper towel, or waxed paper.
4.
Measure each bear
(in cm), and record on the data table
*Lengthwise (from top to
bottom)
*Width (side to side)
*Height (front to back)
5. Measure the mass of each bear in
grams, using the mass scale.
6. Create a bar graph of the changes in each
bear, from day 1 and day 2. You can either graph mass, or volume. Or both. Remember
your TAILS Checklist. Complete the graph on a separate piece of paper. Turn in
when completed.
7. Answer the lab questions & turn in
this lab sheet.
Data Table for Volume:
|
Dimensions for Volume in CM
|
Gummy Bear 1 Color________
TAP WATER
|
Gummy Bear 2 Color_______
TAP WATER WITH SALT
|
Gummy Bear 3 Color________
DISTILLED WATER
|
Gummy Bear 4 Color________
DISTILLED WATER WITH SALT
|
||||
|
|
Initial:
Before soaking in TAP WATER
Day 1
|
Final:
After soaking in TAP WATER
Day 2
|
Initial: Final:
|
Initial:
Before soaking in DISTILLED WATER
Day 1
|
Final:
After soaking in DISTILLED WATER
Day 2
|
Initial: Before soaking in DISTILLED WATER WITH SALT
Day 1
|
Final: After soaking in DISTILLED WATER WITH SALT
Day 2
|
|
|
Length
(cm)
|
|
|
|
|
|
|
|
|
|
Width
(cm)
|
|
|
|
|
|
|
|
|
|
Height
(cm)
|
|
|
|
|
|
|
|
|
|
Volume
(cm3)
L
x W x H = _____cm3
|
|
|
|
|
|
|
|
|
Data
Table for Mass:
|
Mass
(in grams)
|
Gummy Bear 1 Color________
TAP WATER
|
Gummy Bear 2 Color_______
TAP WATER WITH SALT
|
Gummy Bear 3 Color________
DISTILLED WATER
|
Gummy Bear 4 Color________
DISTILLED WATER WITH SALT
|
|||
|
|
|
|
|
Initial:
Before soaking in DISTILLED WATER
Day 1
|
Final:
After soaking in DISTILLED WATER
Day 2
|
Initial: Before soaking in DISTILLED WATER WITH SALT
Day 1
|
Final: After soaking in DISTILLED WATER WITH SALT
Day 2
|
|
Gummy
Bear Mass
|
|
|
|
|
|
|
|
Analysis:
To
find the final mass
Final
mass – initial mass
De
