Nitroglycerine explosive power

Nitroglycerine, a powerful explosive, is an ester of the inorganic acid HNO, and glycerol (glycerine). 

This base is used to the minimum possible extent in the final explosive as the water it contains does not contribute to the power and indeed requires energy for its evaporation. All slurry explosives therefore contain further ammonium nitrate in solid form and also a fuel for combustion. The ammonium nitrate is usually in dense form similar to that used in nitroglycerine explosives as this gives the best physical properties. However, it is common practice to mix the explosive hot so that much or all of the solid ammonium nitrate results from crystallisation during cooling. 

The problem of lowering the freezing point of nitroglycerine has been solved in many ways. Most of these methods are now of historical interest only, since they involved the use of substances which either weakened the explosive power of the nitroglycerine significantly or increased the price of product appreciably. 

The explosion of this mixture which was proposed by Vender [22] as an additive to nitroglycerine in the manufacture low-freezing dynamites produces approximately 90% of the explosive power of nitroglycerine. 

Pure tetranitrodiglycerol is a very viscous oil, which is non-hygro-scopic, insoluble in water, and readily soluble in alcohol and ether. It has a lower explosive power than nitroglycerine, is less sensitive to impact, and its gelatinizing effect on nitrocellulose is not as satisfactory. 

Substances like nitroglycerine are powerful explosives partially because they are chemically unstable. Use the following equation and concepts of energy, entropy, and spontaneity to explain why nitroglycerine is unstable. 

In many respects the use of nitromannite is similar to the use of nitroglycerin. It requires about the same amount of force to set it off, and it delivers about the same yield of explosive power when compacted to rock form. There is a large difference, however, caused by the fact that nitromannitol is a fluffy solid, whereas nitro is a liquid. This fluffiness means that nitromannite is nowhere near as dense as nitro is. As was mentioned earlier, to get maximum detonation velocity, and therefore explosive power, the explosive must be as dense as possible. So the big problem with nitromannite is to get its density high enough to deliver its full explosive potential. 

Whether it is a -C-NO2, -O-NO2, or -N-NO2 link, all these structural features yield substances that are high explosives. Nitroglycerine, cyclonite, pentaerythrytol tetranitrate, tetryl, trinitrobenzene, trinitro-tolnene, and pentanitroaniline are examples of high explosives. The terms high explosives and low explosives are used for qualitative comparisons only. The explosive power of chemicals or their compositions is determined by their brisance and detonation velocity (see. Part A in Section IV). 

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