Coke_&_Mentos

The experiment of combining mentos and soda has been one of the most popular experiments of the early twenty-first century. Such a popularity was initiated by Steve Spangler, who, in both 2002 and 2005, appeared on television to demonstrate what had then become an internet phenomenon. Later on, the experiment was further popularized by the website Eepybird.com, which featured the widely known video starring Fritz Grobe and Stephen Voltz, who were presenting a demonstration of numerous Coke bottles and mentos going off in a timely manner. Being viewed over ten million times at the time of its creation, the video earned a total of $50,000, making it one of the most highly profitable clips of the time. One of the biggest trends in modern-day America is to set the record for the biggest display of soda geysers simultaneously reacting. According to the Guinness World Record, the latest record for this feat was set on June 19, 2008, for the total of 1,911 simultaneous geysers. So, what do you need to create this explosion of soda foam' One material you need is a roll of mentos. Mentos have an oblate spheroid shape, meaning that, in simple terms, they look like spheres that have been pressed down a slight bit. Their exteriors are hard, containing inside a softer interior. For this experiment, regular mint mentos work the best, simply because the other varieties of mento are coated with a layer of flavoring, which slows the reaction between the carbonated beverage and the chewable mint candy. The reason for this will be explained shortly. The second, and only other, ingredient you will need for this experiment is a two-liter bottle containing any carbonated beverage. As many past demonstrations, as well as my own experiments, have shown, Diet Coke seems to work the best with the mentos to create a glorious geyser. To understand how mentos react with soda in the first place, we must break down the composition of the latter. In most, if not all, cases, soda is comprised of sugar (or some other form of sweetening), flavoring (typically unnatural), water, and preservatives. During the process of creating a bottle of soda, a factory will use tons of pressure to pour into the small bottle lots of carbon dioxide gas, which causes the soda to become bubbly. This gas will generally remain in the bottle until it is opened; otherwise, the gas is trapped within the liquid, and, therefore, cannot create bubbles, as it would naturally do. There are two different ways to let the carbon dioxide gas escape from the bottle: either by opening the bottle of soda or by dropping something into the soda. In the former’s case, the water molecules release the gas, which escapes and carries along with it some soda. In the latter’s case, bubbles are immediately formed on the surface of the object which was dropped into the carbonated beverage. This second method of releasing the carbon dioxide gas from the soda is how, according to many people and scientists, the fountain is formed between soda and mentos. However, the reason for this reaction has always been, and still is, disputed amongst many individuals. In fact, one scientist in particular, Lee Marek, holds the notion that the reaction between mentos and soda is a physical reaction, not a chemical one. The reason for this thinking rests with the fact that each mento candy has hundreds, if not thousands, of indentions scattered across its outer surface. The relatively large surface area of the confection also results in a mento having even more of these indentions than, for example, an M&M candy. The nooks and crannies are referred to as nucleation sites, which, during the process of nucleation, are the main catalysts behind the geyser reaction. During this process, a sort of “mesh” of water molecules is formed around each indention, forming a pocket of air which is then released due to gravitational pull and the density of the air, which contains oxygen, versus the density of the surrounding carbonated liquid. Each bubble formed contains a bit of the trapped carbon dioxide gas, which is why, when you drop something into a bottle of soda, the gas is released via fizzing and bubbling. In 2006, the popular television series, Mythbusters, hosted an episode in which a group of scientists conducted the classical Coke and mentos experiment in the hopes of discovering why the reaction occurred. In addition to the physical characteristics of mentos candies, the chemical composition of soda was found to have a role in aiding the reaction. The Mythbusters found that ngredients such as aspartame, caffeine, potassium benzoate, and the trapped carbon dioxide gas in the soda, as well as the gelatin and gum Arabic on the mentos, all react at once to create an explosion of carbonated foam. However, the reactions between these ingredients are only part of the reason as to why the foam flies when you pour mentos into soda. If you have ever performed this experiment to witness the amazing fountain for yourself, you were probable surprised at the rapidity of the reaction. The reason for this quickness has to do with, again, the physical properties of the mentos candies. They have a density greater than that of the soda they are dropped in, which means that they will immediately drop to the bottom of the bottle. Since that’s the case, all of the liquid in that container is at the mercy of the carbon dioxide gas that is released from the liquid. The gas literally pushes all, or most, of the liquid toward the top of the bottle, thus resulting in an inevitable explosion. There have been stories and tales of those individuals who have been hurt due to the rapid explosion of mentos and soda. But, as can be testified from personal experience, these stories are all hoaxes, since the only thing you will receive from this combination is a slight bubbling and fizzing in the mouth.