Journey to the World of Science: Between Physics and Chemistry

Most people know about the famous coke and mentos issue. However, do you know why? This Mythbusters video explains in detail. Unfortunately, I could not embed it here due to company policies of Discovery Channel.

http://www.youtube.com/watch?v=kMXPOqovSBs

Basically, this is what happens:

The ingredients required to create the sensational explosion is as follows.

1. CO2 gas found in soft drinks

2. Artificial Sweetener (which is why diet coke is better than normal coke)

3. Gum Arabic

4. Gelatin

5. The process of Nucleation. Mentos surface is full of tiny craters, and during this process the aforementioned ingredients interact with each other, causing the CO2 to escape to the surface. This is evident from the fact that non-mint mentos, with a waxed surface, reacts very slowly or not at all as the wax covers the craters.

This is also linked to Ms. Liang's post on the discussion forum. Ms. Liang posted on the discussion forum about a Pepsi and Necco wafer experiment. According to the video, Necco wafers release the hydrogen component from hydrogen hydroxide, which is a fancy name for water. Hydrogen is highly flammable, thus fire can form on the surface of the glass.

Necco wafers consist of: sugar, corn syrup, gelatin, gum, colorings and flavorings. From the ingredients, you can tell that Necco wafers are more of powdery candy than wafers as there is no flour in it. I think this would be an interesting experiment to try. However, Necco wafers are manufactured in the USA, so it would be hard to obtain them here in Singapore. Thus, to try this experiment, one could just add gum and gelatin to Pepsi as the other ingredients are redundant. These are pics of necco wafers below.