What makes cooldrink fizzy?

Published on August 25th, 2011
What makes cooldrink fizzy?

One of the best sounds in the world has to be the sound of opening a can of cold fizzy cooldrink on a hot summer’s day. We thought we’d explore what causes that sound.

According to an article on www.lifeslittlemysteries.com, the fizz that bubbles up when you crack open a can of cooldrink is carbon dioxide gas (CO2). As the article says, “The “fssst” you hear is millions of carbon dioxide molecules bursting out of their sweet, watery prisons, where they have been held against their will.”

In fact, did you know that an unopened can of cooldrink is virtually bubble-free because the pressure inside the can keeps the carbon dioxide dissolved in the liquid. It’s only once you open the can that you release the pressure and allow the gas bubbles to wiggle free from the liquid and rise to the surface. “This requires energy because in order for the gas to break free from the liquid it has to overcome the force holding the liquid together”, states the article.

A way to put energy into the drink is to of course shake the can, but doing that could turn into a very sticky mess.

Why do you think gassy cooldrink goes flat? Leave your comments below!

Pic credit: dgj103

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