Transcript from Visibility 9-11; A Basic Chemistry Lesson with Dr. Niels Harrit
As recorded on Visibility 9-11 with Michael Wolsey, April 8, 2009
Full interview with notes found here.
Transcript:
Niels H. Harrit on Visibility 9-11
April 10, 2009
Beginning at 17:10 -
Michael Wolsey: Now, I took many classes in college and one of my science requirements that I had to take was indeed an introductory chemistry class, so I am not a complete idiot when it comes to chemistry, but I know that many of the listeners out there may never have taken a college class in chemistry so I thought it might be helpful to…maybe you could give folks a little bit of basic chemistry lesson and lets maybe take a well known chemical reaction that folks can relate to and maybe explain that.
Dr. Niels H. Harrit: The key word is nano thermite. I would split that in two and take the thermite first. Combustion; the campfire burning…because what is happening in the thermite is basically the same thing as when the campfire is burning. Heat is developed and the carbon in the wood is reacting with the oxygen of the atmosphere, and it is basically the same reaction going on in thermite. Wood burning is something that everyone is related to. Ya know wood is basically is carbon, it’s like coal burning. And when coal or gasoline or wood is burning it is reacting with the oxygen of the atmosphere and the reaction develops heat. So there are two to party; there are two ingredients in the reaction and in this case there is the coal and the oxygen and when they react they develop heat. And the reaction means electrons are being moved basically that what it is. Chemistry is the transformation of matter; of stuff. It is basically the same reaction going on in the thermite, except the role played by the oxygen, is now played by rust. And the role played by coal is now played by aluminum. So it’s the same kind of reaction as ordinary combustion it’s just that there are two other actors on the scene. And these actors now comes as tiny particles. When I say tiny, it’s a relative matter because in the classical thermite, you have pulverized rust and you have pulverized aluminum but still the grains are large enough for you to see by eye. This is like what you call flour and sugar. When you make a classical thermite, and this is an old invention from 1893 made by a German chemist called Goldschmidt and he discovered when he mixed finely divided rust with finely divided aluminum and got the reaction going, which is not that easy, I can tell you that, I have done it myself, but once the reaction is going it develops a tremendous heat and this heat is much much bigger than when the campfire is burning because the actors are mixed on beforehand. In the campfire you have to renew the air, the oxygen for the wood or for the coal to burn. And if you, if it doesn’t get enough air it doesn’t burn very hot, but in the thermite, these two actors who are to react with each other are mixed on beforehand as two powders. But in the plain thermite, these powders are relatively course; we are from a millimeter down to 1/1000th of a millimeter. Now in nano thermite the grains, the particles is much smaller which means that the two actors, the two who have to react with each other are much much more finely divided and they can interact much more intimately and much faster. So the energy developed as heat is now developed so fast that we are approaching what you might call an explosive. You can even make it an explosive by mixing in other stuff and that is the key of the nano. This is the way you make the particles and when you make the particles so small you have the opportunity to mix in other stuff and it is this other stuff that makes it an explosive because in order to be an explosive you have to develop gasses. An explosive is working because it reacts so fast, not because there are terribly much energy but it develops an enormous pressure so you kinda knock over, whether it’s a piece of concrete or it’s a steel beam, you knock it over by force. But the thermite can do both. It depends of the composition of the thermite. It can either develop heat or it can be designed to work as explosive. It can also be, what you call a rocket propellant, what you call rocket fuel like the boosters on the, what you call the Space Shuttle. This is nano thermite. So this is a third option for a version or category of nano thermite which develop a lot of gasses but pretty slowly for the boosters to raise the Space Shuttle into space. But if this reaction is very fast, you get a very high pressure and that is an explosive. So the nano thermite concept has the whole potential and those who are making new explosives for the American military, in their advertisements they call these materials for explosives, the call them smaller, cheaper, and nastier. This is the explosives of the future, this is the munitions of the future, there is no doubt about this.
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