Explosives for kids...just kidding!

Joshua is fascinated with explosives at the moment. He is constantly talking and scheming about how to make gun-powder and other explosives. So for homeschool this week he wanted to do some science with explosives. He has done the vinegar and bicarb experiments, but as a friend brought over pepsi - which we do not drink, he wanted to try the coke (or in this case pepsi) and mentos experiment. What he actually wanted to do was make a rocket airbourne, but it just did not seem to work out like that.

So the theory is... diet coke and approximately 3 mentos are combined and as you can see there is a bit of a chemical reaction. We googled a few versions of this experiment and found a great rocket version and a crazy car powered by coke and mentos.

There is actually a bit of science behind it all as well. Apparently this explosive recipe is not a simple acid-base reaction like the vinegar and bicarb, but is caused by the rough surface of the mentos disrupting the water molecules and creating bubbles as a result. We also discovered that diet coke is better than normal coke due to the effect of the sweetener aspartame which creates more of a reaction than sugar.

Resources
The science behind the experiment