• Question: why does a polo mint explode when you drop it in coke?

    Asked by tarporleyemma7y3 to Duncan, Grant, Julie, Nik, Rachel on 12 Mar 2013.
    • Photo: Grant Campbell

      Grant Campbell answered on 12 Mar 2013:

      Thanks, Emma. The Coke has lots of carbon dioxide gas dissolved in it, wanting to get out. To get out it has to form bubbles, but forming a bubble is quite difficult – you need a starting point such as putting in some energy (which is why shaking the Coke before opening it will also cause it to fizz violently) or something that has lots of tiny rough surfaces that bubbles can grow on. That’s what the polo mint is doing – provinding lots of these tiny starting points. Sometimes beer glasses will have rough patterns engraved on the bottom, to do the same thing – the rough surface of the engraving gives places for bubbles to be created in order to give some control over how the beer will look in the glass.

      Aren’t bubbles interesting!?

    • Photo: Duncan Gaskin

      Duncan Gaskin answered on 17 Mar 2013:

      Grant has answered this much better than I could! But if you wanted to test the theory, you could try different sweets to see which is best – I reckon something rough like Extra Strong Mints might be pretty good.

Comments