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  • today, I want to you a pair of reactions that I think demonstrate really quite nicely.

  • The difference between detonation on dhe d Fla.

  • Gration the two sorts of processes that can occur in explosive reactions.

  • When you actually watched them, there isn't a ll that much difference at normal speed.

  • Detonation sounds louder.

  • You put your hands over your ears, but they're both pretty spectacular.

  • So the first reaction, which isn't a detonation, he's a reaction between red phosphorus, the less reactive Calitri.

  • Preposterous.

  • On Dhe Patasse Implore eight, which is used for percussion caps in toy guns and also for the old fashioned guns.

  • When you fired thes muskets and so on, they often use the percussion cap to get it going.

  • This reaction you take a mixture of the two and put it on the surface on the little plate and then hit it with a hammer when the hammer comes down.

  • It has quite a lot of kinetic energy, and some of that kinetic energy is converted into heat by the shockwave, and that is enough to cause the detonation.

  • 321 And as you watch with a hammer coming down as it hits you can see this explosion shooting outside ways when it's left afterwards, the residue you can see a ring of red phosphorus where it has been blown apart.

  • It's called the detonation because it goes off very suddenly.

  • One minute it's sitting there and it's gone, and this is used to set off other explosives.

  • And most explosives need to have a detonator in order to make them go off.

  • The detonator will be a reaction, which is very often fired by mechanical force.

  • For example, the pin.

  • When you're firing a bullet, the detonation is needed to set off the explosion quickly.

  • When you fire a bullet, you want the gun to go off a CZ quickly as possible, or your enemy may be upon you before the bullet has come out.

  • But you don't want the main explosive in the barrel of your gun to go off really quickly because it would just blow the gun apart and you would injure yourself and your enemy would arrive uninjured.

  • The second demonstration is a much more smooth and slow reaction, which is the reaction of cotton wool with liquid oxygen.

  • You've seen us demonstrating this before, but when you've seen it.

  • It has gone with the Great Bush.

  • It will be dark, but okay, yeah, because we've been filming its normal speed.

  • When you film it at high speed, it's much slower on DME or poetic.

  • You see the match slowly approaching the cotton wool, and then the cotton wool begins to warm up inside, partly because the concentration of oxygen is probably higher inside because it's trapped in the fibers and also because the heat can't get out so fast.

  • So you concede the reaction building up, and suddenly the flame comes out, and then the reaction builds up with more and more intensity until it completely washes out that the picture and you have this huge weight screen in front of you.

  • This slow buildup is just what you need, say in a gun barrel.

  • To accelerate the projectile is it's coming out without blowing up the gun itself.

  • But I think in this video, what is nice is that you can see that after this there one or two pieces of the cotton wool that they left almost completely untouched, presumably on the outside.

  • And there's one crazy piece that takes off rather like the lunar module coming off the surface of the moon and disappears out to the top, and then some white pieces gradually come down again.

  • So in terms of watching it, the D Fla gration is really much more interesting.

  • But chemists use the power of explosives by choosing whether they have a Defla grating explosive or a detonating explosive so that they can get the effect they want from the particular use of these explosives.

  • And quite often, the rial effect is using the two together a detonator to get the thing to start just when you want.

  • And then a Defla grating explosive to produce the steady push that you want to propel some sort of project time.

today, I want to you a pair of reactions that I think demonstrate really quite nicely.

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