#2230. Tootsie-Roll Pop Chemistry

Science, level: Middle
Posted Sat Apr 21 15:43:28 PDT 2001 by Cindy Kessler (moonbeamclk@juno.com).
Ellet High School, Akron, Ohio USA
Materials Required: Tootsie Roll Pops, paper arrows and plus signs, colored pencils, worksheets
Activity Time: 1-2 class periods
Concepts Taught: familiarize students with terminology, concepts of atoms, elements, chemical formulas and equations

Name ______________________________ Class _____ Date _________

TOOTSIE-ROLL POPS CHEMISTRY
Atoms and Chemical Formulas Activity

SUPPLIES: Group Name __________________________
Tootsie-Roll Pops
colored pencils Leader ______________________________
wrappers
arrows Supply Manager _______________________
+ signs
textbooks Reader _______________________________

Public Relations ________________________

Assistant to Leader _____________________

·Select three or four partners. Name your Group.

·Decide who in your Group will be the Leader, the Supply Manager, the Reader, and the Public Relations Officer. The Leader appoints other assistants as needed and keeps the group working. The Supply Manager, or "Gopher", is the only one allowed out of their seat to get the materials the Group decides on. The Reader reads the sections of the lab aloud.
The Public Relations Officer is the only person who is allowed get up to talk to other lab groups, and the only person who can ask me the Group's Questions.

·Each Group will get 1 Free Question before the lab starts and 1 Free Question during the Lab, so be sure the question that you ask me is one that you haven't been able to figure out among yourselves or between lab groups. Other questions reduce your scores by 5 points!

·Work as a group, but, as usual, each person will be turning their own lab paper.

·You will each need a Tootsie-Roll Pop.
Make sure all the flavors are different in your lab group
Page 1
If the flavors of Tootsie-Roll Pops represent different atoms or elements,
how many different combinations of Tootsie-Roll Pops can your group find?

Goal: To find more combinations than the other lab groups within
3 minutes (Round 1), and within 5 minutes (Round 2).

Rules: Atleast two Tootsie-Roll Pops must touch each other.
You must draw a picture of each combination below.
(Use the back of this sheet of paper if you need to.)

1. How many different kinds of atoms are represented by the
Tootsie-Roll Pops? ___________________

2. How many different elements are represented by the
Tootsie-Roll Pops? ____________________

3. How many different combinations did your group make? ____________

4. Do you think that any other group had the
same combinations as your group did? __________________________

5. Were there other combinations your group didn't think of?___________

6. What might this activity suggest about elements? __________________

____________________________________________________________

____________________________________________________________
Teacher Check ________
Page 2
WOW! There were so many combinations with the different flavors. If you had more time you could have found many more.
It seems that a few kinds of basic building blocks may be all that are needed to produce many different combinations

7. Draw a picture "description" of one combination.

8. Describe this combination in words. _____________________________
____________________________________________________________

_____________________________________________________________________________________________

Drawing Tootsie-Roll Pops pictures can be tiresome and
time-consuming. There must be an easier way and there is!

·Unwrap the Tootsie-Pop and put it in your mouth.

·Smooth out the wrappers and mentally give each color a symbol.

Grape = G Raspberry = R Cherry = Ch
Chocolate = Cc Orange = Or

·Make three different combinations using the wrappers and describe them using the color-symbols.

9._________________ 10. __________________ 11._______________

Use these symbols to describe the following combinations:

12. orange and chocolate ______________________________________

13. chocolate, grape, and cherry ________________________________

14. grape, raspberry, cherry and orange __________________________
Teacher Check ____
Page 3

Part II

Sets of symbols like GCh, and ROrCc are called formulas. Each symbol represents one kind of atom. Every element is made of the same kind of atom, so each element has a symbol. If you have more than one of the same kind of atom in a formula, you place that number after and a little below the line to show the number of atoms.
The little number is called a subscript. (You don't need to write 1 if there is only one atom--it's understood that if there is no subscript, there is only one atom present in the formula.)

·Get more wrappers or colored paper squares--at least 4 of each
"flavor".

·First arrange the "atoms" in the following combinations. If there is more than one "atom", place the same "atoms" on top of each other, but make sure that you can count how many there are.

·Then, write the formulas for the following combinations.

15. 3 cherries and 5 chocolates _________________________________

16. 1 orange and 2 grapes _____________________________________

17. 4 chocolates, 2 raspberries, and 3 cherries _____________________

18. 3 grapes and 1 orange _____________________________________

Teacher Check _____

Page 4

Part III

19. What is the Law of Conservation of Mass? ___________________

________________________________________________________

________________________________________________________


· Make the following combinations. Compare and record the numbers of "atoms" on each side of the arrow.

____ Or OrR2 + CcG2 ----® OrCcG4 + CcR2 ____ Or
____ R ____ R
____ Cc ____ Cc
____ G ____ G

____ Or CcG + OrR2 ---- OrG2 + CcR ____ Or
____ R ____ R
____ Cc ____ Cc
____ G ____ G

____ Or Or + Ch2 ----® Ch2Or ____ Or
____ Ch ____ Ch

____ G G + R2Ch ----® RChG + R 2 ____ G
____ R ____ R
____ Ch ____ Ch

Teacher Check ____
Page 5

20. What needs to be done to have these combinations of atoms obey
the Law of Conservation of Mass?
________________________________________________________

________________________________________________________

· Make the combinations obey the Law. You can only make both sides equal (balanced) by using whole numbers called coefficients. If you need multiples of the atom, use a coefficient at the beginning of the formula.

· Express these combinations in balanced form.

OrR2 + CcG2 ----® OrCcG4 + CcR2

CcG + OrR2 --- OrG2 + CcR

Or + Ch2 ----® Ch2Or

G + R2Ch ----® RChG + R 2

In this last activity, you observed:
Plus signs show adding things (reactants) together.
An arrow shows the reactants being changed to something new
(products). It is read as "yields".
The plus signs indicate reactants if they are on the "tail" side of
the arrow, and products if they are on the "head" side.
The arrow can point in either direction (or in both directions at the same time in equilibrium reactions).
A chemical equation is an expression in which chemical symbols and
formulas are used to represent a chemical reaction. Coefficients are the only numbers that can be added to a chemical
equation and obey the Law of Conservation of Mass.
Teacher Check _____
Page 6