Question of the Week

Why does ice make fizzy drinks bubble over?

Thu, 8th Aug 2013

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Belle and Megan asked:

We were wondering why a glass of fizzy drink bubbles over when icecubes

are dropped into it? We've found a few different answers on the

internet, but we only trust the Naked Scientists to give us the right one!


Many thanks,

Bella and Meg

from Amsterdam




Gérard::  My name is Gérard Liger-Belair.  I'm a Physics Professor in Reims University in France.  So the physics of the bubbles, it’s my area of expertise.

Hannah::  So yes, perfectly placed.  Display the answer of Bella’s question on why fizzy drinks fizz over when an ice cube is added…

 Gérard::  So, the main reason is that when you have a soda or fizzy water, it mean that the liquid holds carbon dioxide molecules in excess. So, all those carbon dioxide molecule in excess must escape from the liquid medium. But to escape into the form of bubbles, the liquid needs some tiny imperfections in the glass and at the micrometric scale, the surface of the ice cube is not at all smooth. It is full of tiny cracks.  All these imperfections when they will be in touch with the liquid supersaturated with carbon dioxide molecules in excess, so those tiny molecules will be able to produce what we call from the scientific point of view, the nucleation process.  It means that the liquid will be able to nucleate bubbles. This is the reason why when you introduce ice cubes in your soda or in your fizzy water, it will promote a bubbling process.

Hannah::  Thank you, Gérard, Champagne Bubble Physicist based in Reims, France.  So, soda drinks have been carbonated, so they're full of carbon dioxide molecules, floating around in a liquid and that needs to escape.  These carbon dioxide molecules can only form stable bubbles when they land on a surface with minute indentations like the side of a glass or the surface of the liquid.  An ice cube has lots of bubble promoting imperfect surfaces, so lots of bubbles form, causing the glass to fizz over.  You can experiment further with this concept at home, suckle an ice cube to make the surface smoother and then add to the liquid unless bubbles fizz over should occur


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I guess that the ice cools the water, and unlike most substances, when water cool it expands. Expansion releases air dissolved in the water, which bubbles to the top Made from Embryonic Stem, Sat, 31st Aug 2013

If you look at a pace of ice close you will see it has a bunch of nooks and cranes and each one gives the gas in your drink a spot to billed up and get out; making your fizzy drink bubble over. allgoaway, Mon, 2nd Sep 2013

Half right, post above got it spot on imho. BUT water does not expand as it cools It contracts as you would expect.. It expands when it freezes (by about 10%) SimpleEngineer, Thu, 17th Oct 2013

Nerds Shavu, Thu, 9th Jun 2016

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