Monday, March 29, 2010

Science Project



Purposes of the study:

As all know, Coke is not a healthy substance for the human body. This experiment will test the damaging effects of four different liquids by soaking an egg in salt water, vinegar, lemon juice, and Coke-Cola.

Research questions/Hypotheses:

1. Which substance will dissolve the egg shell the quickest?
2. Why is the egg shell affected?
3. Which part of the body would have the same damage as the egg shell?
My hypothesis is the lemon juice and vinegar will have the biggest effects, and the salt water will not affect the egg shell.


Four eggs
Four containers with lids
Lemon Juice
Salt Water

Steps taken:
1. Put one egg in each of the four contains.
2. Pour one liquid on each egg.
3. Place the lid on each container.
4. After three days, remove the lids.
5. Evaluate the egg shells.
6. Write your results and findings.
7. Carefully drain the liquids out of the bowls
8. Pour new liquid over the eggs.
9. Place the lid on each container.
10. After six days, remove the lids.
11. Evaluate the egg shells.
12. Write your results and findings.

Results and Findings:

The third day:
· The egg that soaked in the vinegar had a noticeable decrease in shell. It was, also, swollen.
· The lemon juice started to cause the egg shell to flake apart. There was, also, a noticeable amount on egg shell in the bottom of the bowl.
· The egg soaked in the Coke-Cola was stained brown.
· The salt water seems to have no affect on the egg shell.





Final Results:
· The egg that soaked in vinegar no longer has a shell. The membrane of the egg is the only boundary protecting the yolk. The egg feels firm but has give when pushed.
· The lemon juice has almost eaten a hole in the egg shell. If the egg shell is touched pieces of shell will flake off.
· The egg in the Coke-Cola did not have much of a change between the 3rd day and the 6th day.
· The egg soaking in salt water was not affected.


Discussion and Conclusions:

Vinegar and lemon juice have high levels of acid. The vinegar contains an acid called acetic acid, and the lemon juice contains citric acid. Both liquids had a great affect on the egg shell. The vinegar (acetic acid) completely dissolved the egg shell only leaving the membrane as a protector. The lemon juice (citric acid) did not dissolve the egg shell, but it caused the shell to crumb away from the membrane.
If farther you would like to try this experiment, trying Diet Coke-Cola could be substitute for the regular Coke-Cola.
When compared to the human body, the eggshell is like the enamel on teeth. The vinegar and lemon juice would damage the enamel if consumed in large amounts repetitively. The Coke-Cola will not damage the enamel, but it will stain the enamel causing a brown, dull smile.

Reference and extended resources or acknowledgment:



  1. This is a great experiment...very interesting topic.

  2. Great idea! I need to stop eating lemons so much..alot of enamel damage. I also try to drink clear soda instead of darker ones. Good job!

  3. I love this experiment and you had some great results. Thanks for bringing the eggs to class so we could see the final product. Maybe this experiment would really make kids stop and think about what liquids can do to their teeth. Nice pictures too!

  4. Thanks for your experiment julie! i'm currently using vinegar to make holes at either end of a goose egg prior to Easter decorating and wondered if lemon juice would be quicker. you result suggests not. this is a great help :-)