When you open the bottle you should hear a gentle fizz. When you pour the drink into a glass you get a bigger fizz and lots of bubbles. If you had ice in the glass you would get even more bubbles. This is because the surface of the glass and the ice cubes are full of little gullies and points. The gas bubbles that were hidden in the liquid attach themselves to the gullies and start to get bigger, (bubbles grow by being joined by other bubbles) and bigger and then when they are big enough, because they are lighter than the liquid, they rise to the surface.
Here is a little experiment for you to try —put the ice cube in your mouth and get your tongue to smooth it, for a few minutes. Think about what I have said and try and predict what the outcome will be when you pour a new bottle of drink over it. Now add the carbonated drink and test your prediction.
Now what happens if you shake the bottle before opening it. This is where you get the explosion! Here is my possible explanation……. look at the bottle of drink.
(1) There is an empty space at the top of the bottle. It’s not empty, it is full of Carbon Dioxide gas.
(2) When you shake the bottle that gas mixes with the liquid and because bubbles attract other bubbles the gas in the liquid becomes more bubbly.
(3) The bubbles that were hidden in the liquid join the new shaken bubbles. Undo the top and these new bigger bubbles all escape at the same time pushing the liquid before it – the explosion.
Look at this previous post.