WEBVTT - What is dynamite? How does it work?

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<v Speaker 1>Welcome to Brainstuff from house Stuff Works dot com where

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

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<v Speaker 1>is dynamite and how does it work? Dynamite is one

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<v Speaker 1>example of a chemical explosive, and explosive is anything that,

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<v Speaker 1>once ignited, burns extremely rapidly and produces a large amount

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<v Speaker 1>of hot gas in the process. The hot gas expands

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<v Speaker 1>very quickly and applies pressure. Other explosives that you commonly

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<v Speaker 1>hear about our nitroglycerin and TNT, but anything from gasoline

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<v Speaker 1>to ammonium nitrate fertilizer to special plastic explosives are in

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<v Speaker 1>the same class. Gasoline is what we are probably most

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<v Speaker 1>familiar with, so let's start with it. Gasoline is made

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<v Speaker 1>up of hydrogen and carbon atoms in chains. If you

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<v Speaker 1>ignite a quantity of gasoline, it burns dreamly rapidly. Oxygen

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<v Speaker 1>in the air combines with the hydrogen and carbon atoms

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<v Speaker 1>to create CO two gas and H two O vapor,

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<v Speaker 1>along with a lot of heat. In large quantities, the

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<v Speaker 1>hot expanding gas creates an expanding pressure wave that can

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<v Speaker 1>blow things apart or in an engine provide useful work.

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<v Speaker 1>Most true explosives contain the oxygen they need for burning

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

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<v Speaker 1>for example, contains carbon and hydrogen like gasoline, but also

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<v Speaker 1>oxygen and a little nitrogen. The carbon and the hydrogen

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<v Speaker 1>combined with that oxygen and the nitrogen is liberated. Dynamite

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<v Speaker 1>is simply some sort of absorbent material, like sawdust soaked

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<v Speaker 1>in nitroglycerin. The absorbent material makes the nitroglycerin much more stable.

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<v Speaker 1>You normally use a blasting cap to detonate dynamite. A

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<v Speaker 1>blasting cap creates a small explosion that triggers the larger

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<v Speaker 1>explosion in the dynamite itself. Be sure to check out

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