Open a soda many meters underground?

Published: 4/8/2020

Author: Andrea Garma

In 2012, astronaut Chris Hadfield starred in a video in which he vigorously shook a small can of soda, however, contrary to what we might assume, the soda does not shoot out. Why does this happen?

It is commonly believed that when a can or a bottle is shaken, it will explode because the internal pressure will increase with movement. However, this information is incorrect. The reason behind this phenomenon comes from the difference between the pressures inside of the bottle and that of the environment where it is opened.

When you shake your soda in a common environment, what happens is that the CO2 bubbles become detached and function as nucleation sites, placing themselves in an escape position attached to the walls, later, due to the pressure difference - the pressure in the exterior is less than that with which the bottle was packaged - the explosive escape effect is generated, achieving an expansion in the bubbles which drive the solution in its movement (Boyle's Law). That is, the bottle will have a reaction, but the pressure inside it does not increase, nor is it because of a reaction, it is a myth.

The producing companies bottle their soft drinks at pressures greater than 1 atm, being under the sea, in the hands of Chris Hadfield, the can is in an environment with a pressure equivalent to 2.5 atm, so the higher pressure of the environment "neutralizes" the explosive effect, despite the agitation, the pressure manages to contain the CO2 bubbles.

Now you know the science behind that everyday phenomenon. Keep eating science cookies with chocolate chips!

References

https://aapt.scitation.org/doi/10.1119/1.2343556

https://www.quimicas.net/2015/07/ley-de-henry-de-los-gases.html

Victims of the pop bottle por Ted Willhoft. New Scientist, 21 de Agosto de 1986. p.28