How the Amount of Mentos Affects the Height of Eruptions

10 Mentos Erupts .08% Higher Than 5 Mentos in Comparison to

Various Amounts of Mentos

Megan D, Kay H & Mackenzie C

Summary:

         The eruption of Mentos and Diet Coke is caused by the reaction of the ingredients: gum Arabic, gelatin, caffeine, potassium benzoate, aspartame, and CO2. The ingredients in the candy and the soda, the roughness of the candy, the temperature of the soda and the amount of Mentos used in the experiment all can be altered to affect the eruption height of the reaction. In this experiment, various amounts of Mint Mentos were tested to see how it affected the eruption height.  After testing this, the results showed that 10 Mentos had the highest eruption (210.8 cm) out of 5 Mentos (209 cm), and 7 Mentos (190.7 cm).

Introduction:

         The experiment involving the reaction between Mentos and Diet Coke has been tested many times before. The Diet Coke and Mentos eruption is when Mentos mint candy is dropped into a bottle of Diet coke causing the soda to erupt and spray out of the bottle. This experiment has been tested many times before, with different tested variables such as soda brands, type of Mentos, nozzle size, drop height, temperature of the soda, sound pitch and volume. For our own experiment, we tested various amounts of Mentos (5, 7 and 10) to see which amount caused the highest eruption. To conclude the experiment, it was discovered that 10 Mentos caused the highest eruption, as previously predicted. It was assumed that 10 Mentos would cause the eruption height to be the highest because of the extra-added ingredients that cause the reaction. This would then cause a bigger reaction, which would in turn lead to a more intense eruption. We compared our results to three experiments conducted by Matt Feldman and Alex Monte, Craig A., T.J. and Luke. Contrasting this experiment to these very similar experiments caused this procedure to show there were multiple errors made because of the vast difference of the results. 1

Experimental Procedure: 

  1. Gather 18 17 fl. Oz bottles of Diet Coke, 18 rolls of Mint Mentos candy, a geyser tube and sturdy base
  2. Find a clear spot near a tall, open brick wall
  3. Place 5 Mentos in geyser tube
  4. Be sure the red stopper is in place to prevent the Mentos from falling
  5. Screw the geyser tube onto the top of the soda bottle
  6. Place the bottle on the sturdy base at a decent angle to allow the soda to spray against the wall so the spray height is clear
  7. Quickly and swiftly pull the geyser stopper to allow the Mentos to fall into the bottle
  8. Measure the height of one brick
  9. Count the number of bricks to calculate the spray height
  10. Multiply the number of bricks by the height of each individual brick
  11. Repeat steps 3-9 with 7 Mentos and new bottle of diet coke
  12. Repeat steps 3-9 with 10 Mentos and new bottle of diet coke
  13. Record all data into a clear and concise table

Results:

        This graph indicates that typically the more Mentos entered into the diet the coke, the higher the eruption height. However, due to multiple errors, 7 Mentos only reached 190.7 cm whilst 5 Mentos reached a whopping 209 cm. 10 Mentos only reached 210.8 cm.

Conclusion: 

        After completing the three trials of the experiment, it was determined that the more Mentos added to a 17 fl oz. bottle of diet coke does affect the eruption height; however, it may not necessarily affect the results in a positive way. There is a plentiful amount of room for error to occur when conducting a type of experiment such as this one. The greatest reason found for error was due to the slant necessary in order for the soda to spray correctly against the wall. It is important to note a discovery such as this one because most times one would assume the more Mentos would always cause a great eruption height. Typically it will, but not always and the data from this experiment is clear proof of this statement.

        In a similar experiment testing how the amount of Mentos affects the height of the Eruption, Matt Feldman and Alex Monte found that for every trial when the number of Mentos was increased, so was the eruption height. This is a nice example of an experiment that had data in which followed through with the general assumption for this particular experiment. After looking at another experiment by Craig A, we noticed that our data slightly differed from his. He reached 302 cm and 258 cm; our highest eruption height was 211 cm with 10 Mentos.  Craig never stated how many Mentos were used during his experiment, but it couldn’t have exceeded 10 Mentos because that is the maximum amount that would fit into the geyser tube. Therefore, there was error that took place during our experiment considering Craig’s experiment is the second set of data that doesn’t compare similarly to ours. Finally, in a third experiment performed by T.J and Luke, their experiment was very similar to ours. They tested the eruption height on 5, 7, 9 and 11 Mentos. They found that 9 Mentos caused the smallest eruption height although it most likely should have been the third highest. This is probably due to error, which is alike, our experiment. However, even though there was error within their experiment, their results were much higher than ours. 5 Mentos for the two boys caused them to reach 473 cm in height while 5 Mentos for ours only reached a mere 209 cm.   It is clear to conclude that our slant was terribly off balance.

        Despite the error that occurred in this specific experiment, the more Mentos should have caused a higher eruption height. It is likely that the reason for this is because a certain chemical reaction occurs between the Mentos and Diet Coke when they are mixed. Therefore, the more Mentos added, it is only fueling to the reaction. The potassium benzoate, aspartame, and CO2 gas contained in the Diet Coke, in combination with the gelatin and gum Arabic ingredients of the Mentos, all contribute to the formation of the foam. When more of these ingredients are added, it is almost guaranteed a higher eruption; however, if there is error it will drastically change the results as it did to this experiment. Perhaps if more trials had been added while testing the height the data would be more accurate.

 Craig A. The Effect of Various Mentos Has On Coke. Guilford Journal of Chemistry. Volume 5. Pages 6-7. (2011)

2 Coffey, Tonya. Diet Coke and Mentos: What is really behind this physical reaction? American Journal of Physics. Volume 76, Issue 6, pp. 551. (2008)

3 Matt Feldman and Alex Monte. How the Amount of Mentos Effects the Height of the Eruption. Guilford Journal of Chemistry. Volume 2. Pages 30-31. (2008)

4 Craig A. The Effect of Various Mentos Has On Coke. Guilford Journal of Chemistry. Volume 5. Pages 6-7. (2011)

5 T.J W., Luke Nerney. The Effect of Putting 5,7,9, and 11 Mentos to Change the Height the Soda Erupts to 92 Bricks. Guilford Journal of Chemistry. Volume 6. Pages 64-66. (2012)

6 Vrannica, Susan. Mixing Diet Coke and Mentos Makes a Gusher of Publicity. The Wall Street Journal Online. Volume 1. Page 21. (2006)