While the policy to not discuss explosives on this forum is very reasonable and makes total sense; what I have seen is that people do not actually understand what an explosive is, hence mods randomly lump discussions of exothermic reactions into the "forbidden" territory.
To clarify: thermite is NOT an explosive.
The accepted definition of an explosive is a compound such that the exothermic chemical reaction propagates through it at the speed of sound or faster. If the chemical is unstable and shock can cause it to react, like nitroglycerin then it would fall under explosives definition. Additionally "Low Explosives" is a subset of chemicals which undergo exothermic reaction slower than speed of sound, however they also release large quantities of gasses, hence creating a large pressure zone.
Gun powder, thermite and many other exothermic reaction, which are indeed exothermic enough to be dangerous, are NOT explosives. The reason for using speed of sound as the dividing criteria is that the shock wave will propagate at the speed of sound, hence dispersing unreacted chemical and reducing energy density in the original volume.
To be more precise the two reactions in question are deflagation and detonation. There is a clear cut definition of what makes something undergo a detonation reaction, while a deflagation reaction is much harder to classify as an explosive, because it must also produce large quantities of gas and happen "fast enough" to not be a "decomposition" reaction.Nitrate are often used in defladation mixtures, however there is a LOOOOOOONG way to go from having a nitrate salt and making it go boom.
In today's world, many "mean" things can be mixed up with a basic chemistry set and a trip to home depot or other hardware store. So, if the goal is to prevent people from being able to mix up nasty compounds, then we need to stop talking about chemistry altogether. We could have a list or "mean" chemicals like potassium cyanide, the synthesis of which is not to be discussed, but then the reader can look up the synthesis of such chemicals elsewhere and ask about making precursors to them. Which means precursors would have to be added to the list and so on. Eventually we'd have to stop discussing chemistry altogether.
I think the things which should be forbidden under "explosives" clause are the following 2 items:
1. No discussions of synthesis of compounds which can detonate. These are the chemicals that have exothermic chemical reaction that propagates faster than speed of sound in the chemicals.
2. No discussions of means or methods about how to make a chemical that undergoes deflagation reaction to produce a pressure gradient larger than 100ATM.
I think this should make a much clearer distinction of what should and should not be discussed.
ChemBuddy | 
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Topic: Anyone know where we could get Nitrate Salts or how to make them? (Read 5109 times)