1. Andrew O’Leary
November 28, 2011
Period 4

2. Problem
 What are the effect of soda on tooth
enamel?

3. Hypotheses
 The darker colored soda has more corrosive
effects than lighter colored soda. The pennies
left in the darker colored soda will look less
tarnished than the pennies in lighter soda.

4. Abstract
 The purpose of this project was to determine the effects of soda on
corrosion of the tooth enamel. The project was to determine which
sodas caused more corrosion; lighter colored or darker colored.
 The hypotheses of the project were that the darker colored soda has
more corrosive effects than lighter colored soda. The pennies left in
the darker colored soda will look less tarnished than the pennies in
lighter soda.
 The first part of the procedures in this project was to locate six
pennies with the same amount of tarnish on them. Each penny was
placed in a cup with one cup of each soda used. One cup contained
distilled water and the others contained Coke, Dr. Pepper, Sprite,
Mountain Dew, and Pepsi. The pennies were placed in each cup and left
for seven days. Each day in the afternoon, the pennies were checked
for corrosiveness or amount of tarnish worn off the penny. Each penny
was dried off and laid on a white note card and given a numerical
measure of 0-10. All of the pennies started out with the rating of 10,
meaning the most amount of tarnish and a 0 rating was no tarnish left.
The pennies were photographed on the first and last day.

5. Variables, Constants,&
Controls
 Manipulated Variable: The type of soda in the cup.
 Responding Variable: The amount of corrosion on the
penny.
 Constants: The amount of soda in the cup.
The amount of tarnish on the penny.
The size of the cup.
The amount of time the penny spends in the soda.
 Control: One cup filled with distilled water.

6. Materials
 1 small bottle of Coca Cola
 1 small bottle of Pepsi
 1 small bottle of Dr. Pepper
 1 small bottle of Sprite
 1 small bottle of Mountain Dew
 1 small bottle of distilled water
 Six plastic cups
 Six tarnished pennies
 Journal or Logbook
 Measuring cup
 Permanent marker for labeling

7. Procedures
1. Fill a plastic cup with 1 cup (measured) of the
Coca Cola soft drink. Make sure each cup is
labeled with the liquid that is contained within it.
2. Repeat step one with the remainder of the
cups, filling each one with a different soft drink
and finally, the water.
3. Drop each of the tarnished pennies in a separate
cup. The penny that is soaking in the cup of
distilled water will be your control.

8. Graph

9. Corrosion Chart Key = 10 tarnish
1 No tarnish
Date Dr. Mountain Coke Distilled Pepsi Sprite
Pepper Dew Water
10/24/2011 10 10 10 10 10 10
10/25/2011 5 9 4 10 7 8
10/26/2011 2 8 2 10 6 6
10/27/2011 1 8 1 10 5 4
10/28/2011 0 8 1 10 4 3
10/29/2011 0 7 0 10 4 3
10/30/2011 0 7 0 10 4 3
10/31/2011 0 7 0 10 4 3

10. Conclusion
 The conclusion of the project is that the darker
colored sodas did cause more corrosion overall
than the lighter colored sodas. Although Pepsi did
not have as much corrosion as Dr. Pepper and Coke
and Sprite had more corrosion than Pepsi, it
cannot be determined that darker colored sodas
cause more corrosion.