 An American 25 cent piece, a quarter, is composed of a copper core and a coating of an alloy made of 75% copper and 25% nickel. What we're going to do here is heat up the coin and drop it into methanol. What I have over here is our safety device in case the methanol flames up, then we have a wet piece of wood that will cover that. Okay, so first thing we're going to do is to heat the quarter. We want it to be very, very hot. It's glowing pink and so hot it's boiling the methanol. Now watch what happens when we think the reaction has come to closure. Our quarter now has a copper coating. What happens is when the copper is coming out of the alloy that is an exothermic reaction and that second set of bubbles you see is the exothermic release of the copper from the copper nickel alloy.