We have all been played a joke at one time can of freshly stirred soda to see how our faces are filled with foam and shame.
So sometimes when we pick up one of these cans we take a thousand precautions, like waiting for it to settle, opening it to a considerable distance of our face or give him some tapping on top, in order to avoid explosive foam outlet.
The latter is one of those customs that are learned and done, despite not being sure about its effectiveness. So a professor of chemistry at the Nottingham Trent University, has written an article in The Conversation in which he talks about the process by which the bubbles and its possible relation to the ritual of tapping.
What is the cause of the bubbles coming out of a can of soda?
As you know, the contents of the cans of carbonated drinks it’s found locked under pressure, so when the container is opened, a abrupt decrease of this pressure.
Well, all this leads to a change of carbon dioxide solubility that leads to the bubbles that were glued to the walls become larger by decreasing the pressure, gradually reaching a concrete size that leads them to move to the top of the can, dragging the liquid with them.
If the drink is not stirred the opening of the container will only give rise to that little whistle characteristic that we all know, but if someone funny has shaken it or just moved on the way from the supermarket to home, for example, there will be more bubbles and will drag more liquid with them.
Is there any use then tapping the can lightly to prevent the foam from leaking into our faces?
According to Chirs Hamlett, chemist of the Nottignham Trent Universitytapping the can gently can help displace some of those bubbles, preventing them from coming out abruptly, but the opacity of the can makes it impossible to know if they have expanded correctly, so the best option is to let the can rest a little or, if the adventurous spirit can, open it to see what happens. After all, how much you will get wet or laugh at you, but it is not something so serious.
