Segment #5 - Chemistry with Diet Coke

Chemistry with Diet Coke
Segment 5

Welcome to the Science Playground! Today we're going to be exploring, CHEMISTRY WITH DIET COKE!

The ingredients you're going to need for this experiment includes:

• 2L Diet Coke Bottle (You might need more than one!)
• Pack of Mentos for Every Bottle 

The materials you're going to need for this experiment include:

• A Pot or Bin to stabilize your bottle
• Toy Nozzle (Optional - helps the experiment run smoothly)

Although today's experiment isn't hazardous, we still recommend that you wear goggles, an apron or lab coat and gloves to protect against spills and splashes. This experiment is super messy, so this experiment should be done outside to prevent angry moms and dads!

Before we start, you will need to stabilize your pop bottle in a bin. If you don't, this reaction can act as a propellent and launch the bottle with a potential to cause injury. I used an old planter pot with some gardening soil to stabilize around the bottle.

The first step is to remove the cap from your Diet Coke bottle. Next, you must place the entire pack of Mentos into the bottle. 

After I had attempted to place the entire pack in, I became fully drenched in a sticky mess of Diet Coke. I found a toy nozzle that could be placed on top of the bottle to see if that would work. You can buy these toy nozzles at toy stores, craft stores or science stores. Once we pulled our string back, the mentos dropped into the soda and created a geyser of coke.

Lets take a look at this experiment a little closer. 

Our Diet Coke is a liquid that has had carbon dioxide put into it. Liquids and gases don't generally like to mix together. The bottles are pressurized, forcing the carbon dioxide to stay dissolved. When the lid is removed, the pressure decreases and the carbon dioxide from the liquid is slowly released into the air. If a carbonated beverage is shaken or stirred, more carbon dioxide than normal is released and causes more bubbles to form and foam. If we drop the Mentos into the bottle of Diet Coke, the Mentos bump into the carbon dioxide molecules, creating the same effect of shaking or stirring the pop, this time at an amplified magnitude. 

Each Mentos has tiny little ridges and pores. These ridges increase the surface area of the pores, allowing them to bump into tons of carbon dioxide molecules. So much of the carbon dioxide is being released, liquid is also forced out of the bottle in the form of foam. This reaction causes a large coke geyser.

Diet Coke creates larger geysers than pops with sugar because the aspartame reduces the forces keeping the carbon dioxide in the liquid and allows for a faster release of the carbon dioxide gas. 

So that's it for today guys! I hope you enjoyed this experiment, stay tuned for our next segment on DENSITY LAYERS!

If you have any questions about this experiment or science in general, feel free to email me at englishprojectscience@gmail.com