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Speaker 1: Welcome to Brainstuff from house Stuff Works dot com where

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Speaker 1: smart happens. Hi Am Marshall Brain with today's question, what

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Speaker 1: is dynamite and how does it work? Dynamite is one

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Speaker 1: example of a chemical explosive, and explosive is anything that,

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Speaker 1: once ignited, burns extremely rapidly and produces a large amount

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Speaker 1: of hot gas in the process. The hot gas expands

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Speaker 1: very quickly and applies pressure. Other explosives that you commonly

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Speaker 1: hear about our nitroglycerin and TNT, but anything from gasoline

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Speaker 1: to ammonium nitrate fertilizer to special plastic explosives are in

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Speaker 1: the same class. Gasoline is what we are probably most

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Speaker 1: familiar with, so let's start with it. Gasoline is made

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Speaker 1: up of hydrogen and carbon atoms in chains. If you

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Speaker 1: ignite a quantity of gasoline, it burns dreamly rapidly. Oxygen

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Speaker 1: in the air combines with the hydrogen and carbon atoms

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Speaker 1: to create CO two gas and H two O vapor,

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Speaker 1: along with a lot of heat. In large quantities, the

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Speaker 1: hot expanding gas creates an expanding pressure wave that can

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Speaker 1: blow things apart or in an engine provide useful work.

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Speaker 1: Most true explosives contain the oxygen they need for burning

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Speaker 1: inside the chemical This allows burning to occur much more quickly. Nitroglycerin,

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Speaker 1: for example, contains carbon and hydrogen like gasoline, but also

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Speaker 1: oxygen and a little nitrogen. The carbon and the hydrogen

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Speaker 1: combined with that oxygen and the nitrogen is liberated. Dynamite

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Speaker 1: is simply some sort of absorbent material, like sawdust soaked

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Speaker 1: in nitroglycerin. The absorbent material makes the nitroglycerin much more stable.

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Speaker 1: You normally use a blasting cap to detonate dynamite. A

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Speaker 1: blasting cap creates a small explosion that triggers the larger

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Speaker 1: explosion in the dynamite itself. Be sure to check out

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