Monday, January 17, 2011

The Mentos Experiment

It's that time of year again... Science Fair time!

Last Thursday we watched the Mythbusters Diet Coke & Mentos experiment, where they isolated each ingredient of the soda & candies to try and find out what causes the reaction. We wrote down each step of the scientific method they followed. Then we decided to try our own experiment with Diet Coke & Mentos.

Question: Which will create a higher soda fountain, Diet Coke or Coke Zero?

Research: The Mythbusters found out that several ingredients in the soda caused the reaction...CO2, Aspertame (artificial sweetner) , Potassium Benzoate (preservative), & Caffeine all play a factor in the reaction. Both sodas contain all of these ingredients. The only difference is Diet Coke has more Aspertame than Coke Zero.

Hypothesis: We took a vote and most of our class thought that Diet Coke would create a larger soda fountain, because it has more Aspertame & that was one of the key ingredients identified by the Mythbusters as causing the reaction.

1 We went outside with our soda, candy, & measuring device (2 yardsticks taped together and stuck in a coffee can full of rocks).

2 A volunteer dropped mentos in the Diet Coke and we measured how high it went.

3 Repeat the experiment with the Coke Zero.

Coke Zero: 55 Inches
Diet Coke: 26 Inches

On our first attempt with the Diet Coke the student volunteer dropped the candy in too soon and knocked over the yardstick trying to stop it...only one of the 3 candies made it into the soda, so we only dropped one candy into the Coke Zero (instead of the 3 we had planned on). This could have affected our results.


Coke Zero Fountain.
Sadly, there is no picture of the Diet Coke Fountain
because the candy was prematurely dropped and
Miss Jaster wasn't ready to take the picture!

Our hypothesis was incorrect. Coke Zero made a higher soda fountain than Diet Coke. The AMOUNT of Aspertame must not be as big a factor as we thought.