Does Soda Go Flat Faster When It's Warm?

My husband and I have had an ongoing debate. It drives him crazy, that I leave opened cans of pop on the counter, when they still have pop in them. He always puts his back into the fridge, and maintains they don't go flat as fast that way.

I've always thought that was kind of silly. An open can of soda goes flat no matter what the temperature, and if I put in the fridge, I'll just forget it's there, and won't get to it until it's really flat. But, it turns out, there may be some scientific merit to my husband's argument.

While researching another experiment for the children, also having to do with pop, I read that the carbon dioxide gas, which is what gives soda it's fizz, dissolves easier into a cold liquid, than into a warm liquid. That means, that if the pop is warm, it would more easily release the carbon dioxide, and would go flat faster.

The children and I decided we needed to test the theory with some Mentos. :) We used 8oz bottles of Coke Zero, and only one Mento for each bottle, so we didn't end up with the great big geyser effect you sometimes see.

But, it was enough to test the theory. We hypothesized, that a cold bottle of pop would show less of a reaction than a warm bottle of pop, because the warm pop would more easily release the carbon dioxide to react with the Mentos (just like the with the Pop Rocks, this is a physical reaction, rather than a chemical one).

Warm pop:

Cold pop (and a smaller reaction - in case the picture isn't clear):

So, it appears my husband's argument in favor of keeping opened sodas in the fridge, instead of on the counter, is actually a valid one (drat!).

And, just so you don't get the mistaken impression, that we carry out these experiments in any kind of organized, scientific manner, I've included a video - keeping it real.

For more fun with science, click on over to Adventures in Mommydom, for this weeks Science Sunday link up.

It's great to be a homeschooler.