Chemical or fizzical?

Want to create a cola explosion?

How cool? Cola fountains that compete with the Las Vegas Bellagio hotel's fountain show!

Take a look at the video clip to see the experiment in action!

Launch the video in another window.

So what's happening? You'd think it was a chemical reaction, wouldn't you..?

Co 3L2 A4+ Me.n2To3S2? Carbon dioxide gas - GFX

Sorry to disappoint you, but it's not.

What actually happens is that the carbon dioxide (CO2) gas dissolved in the cola is nudged into bubbling out all at the same time. Normally it takes ages to escape keeping your drink fizzy until, hic, you've finished it.

So how do you get the gas out of the cola?

This is what the mentos are really good at doing. They have a special coating that is covered with millions of microscopic pin points. Gas bubbles love to form on pin points.

You have actually seen this happen.

Pour a fizzy drink into a dry glass and it will often bubble up and spill over the side. Champagne does it all the time! This is why traditionally 'bubbly' is poured into tall thin glasses called champagne flutes.

However, once you have got the glass coated with the drink the points are effectively smoothed out and so no more bubbles form. The second time you pour it's easy to fill the glass without spilling too much more fizz! The gas stays put.