Based on the reference provided, the number of Mentos typically added to Coke for the famous geyser experiment is seven.
While there are no Mentos naturally present in a bottle of Coke, the context of dropping Mentos into Coke is widely associated with creating a spectacular soda geyser. The reference details a specific recipe for achieving the "best Mentos Geyser," which serves as the basis for this answer.
Understanding the Mentos and Coke Reaction
The interaction between Mentos candies and carbonated beverages like Diet Coke is a popular science demonstration. It's not a chemical reaction in the traditional sense, but rather a physical process involving nucleation.
- Nucleation Sites: The surface of Mentos candies, particularly the plain variety, is covered in tiny pits (microscopic indentations). These pits act as ideal nucleation sites where carbon dioxide gas molecules dissolved in the soda can rapidly come out of solution and form bubbles.
- Surfactants: The ingredients in Mentos, such as gum arabic, also act as surfactants, which help to lower the surface tension of the water in the soda. This makes it easier for the bubbles to grow and escape.
When a large number of Mentos are dropped into the soda simultaneously, this creates a massive number of nucleation sites, causing the dissolved CO2 to rapidly form bubbles. The density of the Mentos candies also helps them sink quickly to the bottom, maximizing their interaction with the soda.
The Recommended Number of Mentos
According to the experimental recipe detailed in the reference for achieving an optimal geyser effect:
Based on your individual test results, you might have arrived at this recipe for the best Mentos Geyser: Use a bottle of Diet Coke. Make sure the soda is at least 85 degree Fahrenheit. Drop seven Mentos into the soda all at the same time.
This specific instruction clearly indicates that seven Mentos candies are recommended for use in this particular geyser setup described.
Ideal Geyser Setup Elements (Based on Reference):
- Soda Type: Diet Coke is often preferred as it tends to produce a more vigorous reaction due to its composition, though the reference specifically mentions using it for this recipe.
- Soda Temperature: The reference states the soda should be at least 85°F (approximately 29.4°C). Warmer temperatures decrease the solubility of gases, meaning more CO2 is ready to escape.
- Number of Mentos: Seven.
- Delivery Method: Drop all seven Mentos into the soda at the same time to maximize the nucleation rate.
Therefore, when referring to the context of the Mentos and Coke geyser experiment as outlined in the provided reference, the answer to how many Mentos are in the Coke is specifically seven.
