The Explosive Power of Chemicals

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Credit: Moore Memorial Public Library, Texas City

Explosions can be disastrous or useful, depending on when and how they happen. Any fast chemical reaction that produces lots of heat or a large volume of gas is potentially explosive. Its destructive power is due to the resulting shock waves. These are caused either by atmospheric expansion due to the rapidly released heat, or by the fast expansion of the gases produced.

The oldest explosive, gunpowder, is a low explosive whose shock waves travel at about a hundred metres a second. High explosives like TNT, trinitrotoluene, produce shock waves that travel up to six thousand metres a second.

Nitroglycerine is a liquid that explodes twenty-five times faster than gun powder. To make it safer to handle, the famous Swedish inventor, Alfred Nobel, soaked it in clay and called it dynamite.

A stronger explosive than gunpowder is ammonium nitrate, which is also used as a fertilizer. Normally it’s safe, because it has to be detonated before it will explode. However, careless handling of large quantities can cause massive explosions. For example, in 1947 a ship carrying this fertilizer exploded and levelled a huge area of Texas City, claiming five hundred and seventy-six lives.

So next time you drive through a tunnel, be thankful for the amazing power chemically stored in explosives.