How Explosives Work

Explosives simply burn. They contain a fuel, which combines with oxygen, and they simply burn faster than the wood in a campfire. They do their damage primarily because of the large expansion of gas as well as the heat that results from the burning process. 

A simple explosive like black powder is a mixture. The oxygen source is potassium nitrate, and the fuel is charcoal with sulfur added to aid the burning. Flour and air is even a simpler explosive but powerful enough to blow a grain elevator apart. Even the most modem explosives still use a 

Nitroglycerine and later TNT were early explosives in which all the necessary elements were in one molecule. Because the fuel and oxygen source are in one molecule, it can burn faster than a mixture. In essence, TNT has a faster detonation rate of 22,600 feet per second than, say, black powder at 1500 feet per second. 

explosives like TNT are casually referred to as more powerful, although that is an imprecise term. In truth, explosives cannot be measured by a single factor. Detonation velocity is the speed of the reaction. Brisance is the ability to fragment (i.e., the shell casing) it is a combination of density, heat, detonation rate, and gas volume released. 

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