Hey Ray: 'Pop' Science
PITTSBURGH (KDKA) - Have you ever noticed how much science is packed into one can of Pop? Some people call it "soda", but we know in Pittsburgh the word to use is "pop"!
When you pour a glass of that sweet, sweet pop, the unmistakable carbonation creates bubbles and an audible fizz. That fizz continues until you drink all of your pop, or it goes flat.
Obviously, it is carbonated, but why does that cause bubbles and fizz? For beverages to become carbonated, carbon dioxide needs to be dissolved into the liquid under pressure. You hear that pressure release when you pop open the pop can. You can even see a little cloud come out of the can. That is some of the carbon dioxide being released when the pressure drops after you open the can.
Since you dropped the pressure in the can by opening it, the rest of the carbon dioxide starts to seep out of the pop as bubbles and fizz. Remember, the carbon dioxide was forced into the liquid under pressure. When that pressure drops after opening the can, the liquid can't hold onto it, so the excess carbon dioxide is released as bubbles. They pop, causing the fizz at the top.
Now that we know that carbon dioxide is dissolved into pop under pressure, is there something you can do to open a can of pop that has been shaken? For that answer, let's first find out what is happening.
When you pour pop in a glass, you will notice that the bubbles stick to the side of the glass. These bubbles are sticking to imperfections on the glass. Since they are more buoyant than the liquid, eventually they float upward. The same thing happens inside the can. When you shake it up, you essentially distribute those tiny bubbles all through the pop, especially on the sides of the can.
When you pop the top, you introduce oxygen and release the pressure. This causes those little bubbles to escape the solution. As they rise, they lift the pop with it, creating a foamy mess. When the carbon dioxide is dissolved into the liquid it takes a lot longer for it to escape.
To keep the can from exploding all over, the best thing to do is wait a little while before opening the can. The bubbles will dissolve back into the solution.
If you can't wait, flick around the sides of the can. This will push some or most of those bubbles back into the solution and will help to limit the mess.
