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Diet Coke Floats

After the birthday party last weekend, we had a big cooler of cokes (remember, I’m from Arkansas and it’s always coke no matter what variety it may be) and bottled waters left over.

Did you notice anything in the picture? Well, I sure did! All the diet coke products (Diet Coke, Diet 7-up) were floating and the regular cokes (Pepsi, Dr. Pepper) were sunk to the bottom of the cooler.

Why does Diet Coke float?

Well, the answer to this question is related to density and water displacement. Density is the relationship of an object’s mass to its volume. (Is it heavy or light? Big or small?) Water displacement describes how an object pushes aside a liquid when it’s placed into the liquid. An object that is more dense will push aside more liquid and the object will sink. An object that is less dense will push aside less liquid and the object will float.

The regular coke contains ingredients that are more dense … like sugar. The diet coke contains ingredients that are less dense … like artificial sweetners. This is why regular coke sinks and diet coke floats.

Now you know.


Thursday 22nd of October 2020

I had a great test on this experiment can I use you for my prject


Thursday 22nd of October 2020

Yes, you can!


Saturday 27th of June 2009

So glad you liked it! I was just fascinated by this phenomenon. I'm *cough* 30-something and I've never heard of this before in my life!

So much for learning everything you need to know in kindergarten, right?


Saturday 27th of June 2009

hey, thanks, this was pretty interesting, I'm glad you gave the explaination after posing the question. :-)