Dispersement of Particles: Diffusion and Osmosis
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Marge Rockwood Horace Greeley
832 W. Sheridan
Chicago IL 60613
For elementary grades, adaptable for Kindergarten through eight.
Students will be able to describe the many ways in which particles move and
transfer from one source to other areas.
A: vanilla extract, balloon, eye dropper, empty box (shoe box) perfume or
ammonia, fresh popcorn in a paper bag (smelly things)
B: food coloring, water (hot/cold), transparent cups, overhead projector,
C: cooked rice kept moist (undercooked, sticky), liquid starch, newspaper,
Ziploc bags, worksheets
D: corn syrup, salt, water, cup, dialysis tubing
A: Demonstrate to the class: place a few drops of vanilla extract into a
balloon (careful not to drip on outside of balloon) knot balloon closed and
place into the empty box (prove the box is empty and doesn't smell). Set
aside and work on something else. At end of class, open the box and smell
(heavy odor of vanilla). Have the class examine and explain.
Instruct the students to close their eyes and raise their hand the moment
they smell an odor. Spray perfume or open ammonia in front of the room;
record time and number of students that raise their hand. Discuss what was
happening and why. Try other areas and odors in room. Place a fresh paper
bag of popcorn in the room and notice how many students say they smell it.
B: Opt. (Have a glass pie pan filled with water on an overhead and place drops
of food coloring into water and observe.) Each student needs a cup of hot
and a cup of cold water along with food coloring. Instruct them to place
one drop into the cold water and time it until it is uniformly colored
and do the same for hot water. Do worksheet and discuss results. Chart
results on chalkboard.
C: Have students in groups with 4-6 members. Each group has rice in a Ziploc
bag and some newspaper. Cover the floor or desk that they will be working
over. One student will stick their hand in the liquid starch and then in the
bag of rice. With the rice covered, hand shake hands with each remaining
member. They can record data and compare with other groups. First child will
have most rice and the last child to shake hands with the rice person will
have the least. (another way) Similar to a chain link, the rice person will
shake hands with one person and that person shakes hands with the next one in
line until everyone has given a hand shake.
D: Have students in groups with 4-6 members. Each group needs salt, corn syrup,
water, dialysis tubing and two cups. A salt water solution and the corn
syrup are placed in their own dialysis tubing and then placed in each cup.
Fill each cup almost full with water. Let it sit and check it daily for
results. Students should see that water is moving from the clear water into
the tubing which has either salt water or corn syrup. Record and discuss.
I would expect that all the students would be able to successfully complete
and perform the experiments.
I would assess their learning from: observation, discussion, participation
and completion of work sheets.
A: Do you think the vanilla will escape?_________________
How will it escape?_________________________________________________
Did the vanilla escape?____________
Give an explanation for the results.________________________________
B: What will happen when the coloring enters the water?________________
Will the two cups get the same results?_____________________________
If not, why?________________________________________________________
Basis for your reasoning.___________________________________________
start time for cold:____________ end time for cold:_________________
start time for hot:_____________ end time for hot:__________________
Based on your results what was happening and why did it turn out that
C: What is going to happen to the rice when you shake hands?___________
Will there be a difference between the first and last, why?_________
Where and how did the rice travel during the experiment?____________
Results amount of rice on hand amount of rice dropped
FIRST PERSON ______________________ ______________________
SECOND PERSON ______________________ ______________________
THIRD PERSON ______________________ ______________________
FOURTH PERSON ______________________ ______________________
D: What happened inside the dialysis tube with corn syrup?____________________
What happened inside the dialysis tube with salt water?____________________
What happened inside both of the cups?_____________________________________
Students will find out that particles disperse themselves through diffusion and
osmosis. Students will find out that particle movement is affected by movement,
temperature and concentration. The movement of particles from greatest
concentration to lowest concentration is diffusion. Osmosis is the movement of
water through a semi-permeable membrane.