This article comes from Dr. Tonya Coffey and was published in the American Journal of Physics, the article was created and published upon Dr. Coffey's dissatisfaction with the explanation used in a video posted by the Mythbusters which I also utilized. Coffey's s explanation pertains to a chemical reaction in addition to the physical reaction other articles mention.
Coffey believes that the ingredients gum arabic and gelatin found in the Mentos react with the benzoate as well as the aspritane in the diet coke, the reaction lowers the surface tension of the cola at the mouth of the bottle. The reduction of the surface tension will cause for a larger fountain of soda to erupt as the departing molecules use less energy to break the surface tension meaning they will go higher in the air. This explains why diet soda works better than non-diet soda as the aspritane reacts better with the Mentos causing the surface tension to be further reduced than normal soda meaning that the fountain will go significantly higher (see graph).
As do the articles I have summarized, Coffey believes that a large part of this reaction is based on nucleation. As the Mentos have countless tiny dimples in the rough surface, rising C02 particles become trapped in the dimples were they combine with other C02 particles to perform C02 gas bubbles which may be visible by the naked eye. These bubbles are pulled away due to their buoyancy and upon reaching the mouth of the bottle break the surface tension (reduced by the chemical reaction) forcing the soda to erupt into a fountain. The concept of nucleation was further proved by Coffey as she placed crushed Mentos in the soda as the only changed variable resulting in much shorter fountains mainly due to the fact that the C02 no longer had one large surface area but many small surface areas resulting in much smaller bubbles and in turn a much lesser reaction.
After reading all three article, it is my opinion that the article by Dr. Coffey is the most significant article as it combines the points addressed in the other articles while introducing another belief that compliments and supports the other article along with evidence.
Coffey believes that the ingredients gum arabic and gelatin found in the Mentos react with the benzoate as well as the aspritane in the diet coke, the reaction lowers the surface tension of the cola at the mouth of the bottle. The reduction of the surface tension will cause for a larger fountain of soda to erupt as the departing molecules use less energy to break the surface tension meaning they will go higher in the air. This explains why diet soda works better than non-diet soda as the aspritane reacts better with the Mentos causing the surface tension to be further reduced than normal soda meaning that the fountain will go significantly higher (see graph).
As do the articles I have summarized, Coffey believes that a large part of this reaction is based on nucleation. As the Mentos have countless tiny dimples in the rough surface, rising C02 particles become trapped in the dimples were they combine with other C02 particles to perform C02 gas bubbles which may be visible by the naked eye. These bubbles are pulled away due to their buoyancy and upon reaching the mouth of the bottle break the surface tension (reduced by the chemical reaction) forcing the soda to erupt into a fountain. The concept of nucleation was further proved by Coffey as she placed crushed Mentos in the soda as the only changed variable resulting in much shorter fountains mainly due to the fact that the C02 no longer had one large surface area but many small surface areas resulting in much smaller bubbles and in turn a much lesser reaction.
After reading all three article, it is my opinion that the article by Dr. Coffey is the most significant article as it combines the points addressed in the other articles while introducing another belief that compliments and supports the other article along with evidence.