When pouring a carbonated beverage in a glass, there is a steady stream of bubbles all originating from the same spots all around the glass. Why aren’t the bubbles random or evenly distributed?
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In: Chemistry
They’re called nucleation sites, just a minute physical irregularity in the glass that makes it easier for the saturated gas in the drink to collect at and turn into bubbles. It’s like when ice crystals spontaneously start forming on glass .
While CO2 gas can escape from the solution from anywhere, small imperfections on the sides of the glass form what are called nucleation points – places where it is easier for the gas to leave solution and form larger bubbles. As gas escapes, more gas uses the nucleation point to escape afterwards.
That is one of the reasons behind the Mentos-Diet Coke fountains that were all the rage years ago. The Mentos candy is covered in nucleation points, allowing the gas to rapidly escape once submerged.
Bubble formation is called “nucleation”. It is easier for an existing bubble to get bigger than it is for a bubble to form from nothing. If your glass has tiny imperfections in its surface then tiny bubbles can get trapped on the surface of the glass. These trapped tint bubbles are great spots for nucleation. The carbonation in the soda causes them to get bigger until they are so big that they break away and float up to the top of the liquid. But the original trapped bubble is left behind. The process repeats and it will appear that the bubbles are all coming from the same place.
It also works with anything “rough” like a small piece of sand.
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