What causes chemical explosions?
Why do so many chemical reactions give out heat or explode? Where is that energy coming from?
Izzie Clarke asked Chemistry World's Kit Chapman to tackle this explosive question from James on Facebook.
Kit - Well, the energy isn't actually coming from anywhere. We don't make energy. If you know how to make energy, contact me, we'll win the Nobel prize, it'll be fantastic. Energy is just transferred. What's happening here is we're transferring it from the chemicals themselves out into the atmosphere. When you have a chemical reaction this is what we call an exothermic reaction, so something that gives off heat, and what you're doing is breaking up the bonds. So, if you think about it, you've got your molecule, that's atoms attached to each other with bonds, those bonds have to be broken and reformed to make whatever you're making. And so when you break those bonds you're releasing the energy there. When you're reforming the bonds, that takes up less energy usually and so that means that there is energy left over, and that's given away as heat.