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Speaker 1: Welcome to brain Stuff from house stuff works dot com

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Speaker 1: where smart happens. Hi. I'm Marshall Brain with today's question,

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Speaker 1: how does nitroglycerin work? In eighteen forty six, scientists discovered nitroglycerin.

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Speaker 1: It's pretty simple to make. You start with nitric and

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Speaker 1: sulfuric acids in an ice bath and you slowly add

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Speaker 1: glycerin to it. You have to make sure to add

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Speaker 1: the glycerin at a slow enough rate to avoid a

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Speaker 1: temperature rise, because if the temperature rises, you can get

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Speaker 1: an explosion. The nitroglycerin that gets formed creates a layer

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Speaker 1: on top of the acid. If you extract this layer

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Speaker 1: stay with an eye dropper, you have the desired product.

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Speaker 1: It's pretty remarkable stuff, but not very stable. If you

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Speaker 1: take a drop of it and put it on a

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Speaker 1: piece of paper and put that piece of paper on

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Speaker 1: a countertop and tap it with a hammer, it will

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Speaker 1: explode with a loud pop. Just a few grams of

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Speaker 1: nitroglycerin can create an impressive explosion. Why is it explosive?

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Speaker 1: Compare a molecule of gasoline to a molecule of nitroglycerin

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Speaker 1: and you can see why. Gasoline contains eight carbon atoms.

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Speaker 1: And eighteen hydrogen atoms. If you light it, it combines

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Speaker 1: with oxygen in the air to burn. A gallon of

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Speaker 1: gas might produce a fireball when you burn it, but

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Speaker 1: it's not really an explosion because it has to suck

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Speaker 1: in oxygen from the air to burn, and that takes time.

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Speaker 1: A nitroglycer molecule has three carbon atoms, five hydrogen atoms,

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Speaker 1: three nitrogens, and an impressive nine oxygen atoms. In other words,

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Speaker 1: each nitroglycer and molecule contains almost all the oxygen needed

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Speaker 1: for complete combustion, so it can burn much faster explosively. However,

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Speaker 1: the instability of nitroglycerin is a problem. If you drop

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Speaker 1: nitroglycerin or bang it or round, it can explode spontaneously.

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Speaker 1: Alfred Nobel is the first guy to figure out a

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Speaker 1: way to stabilize it. He mixed it with something like

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Speaker 1: sawdust to create dynamite, which is much more stable. For

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Speaker 1: more on this and thousands of other topics, visit how

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Speaker 1: stuff Works dot com. To learn more about the podcast,

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Speaker 1: click on the podcast icon in the upper right corner

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