Page 27 - Curriculum Visions Dynamic Book

Nitroglycerin and dynamite
Glyceryl trinitrate (called nitroglycerin) is the most unstable of the common explosives. It is a pale yellow oil prepared by reacting nitric acid with glycerol (a product of oil refineries).
Alfred Nobel was the first to make a stable form of nitroglycerin by making it into a solid. In this way he created the world’s most widely used high explosive – dynamite.
Ammunition
Nitrogen
explosive: a substance which, when a shock is applied to it, decomposes very rapidly, releasing a very large amount of heat and creating a large volume of gases as a shock wave.
 A representation of a molecule of nitroglycerine
Ammunition is the word used to describe a wide variety of objects that are propelled to their target. Any piece of ammunition will have a primer, or detonator, a propellant, the material that explodes, and a projectile, such as the
shell or bullet. All of this is usually contained in a casing.
Most modern primers are called percussion caps. They contain sensitive explosives that detonate on a shock from, for example, the hammer of a gun.
The main propellant for ammunition is nitrocellulose. This was traditionally called guncotton, because at one time cotton fibres were soaked in liquid explosive. Modern guncotton uses wood fibre.
Projectiles used to be small lead balls. Modern ammunition is clad in brass or copper and is given a more streamlined shape that we recognise as bullets.
TNT
TNT is the abbreviation for trinitrotoluene, the most common high explosive. It is produced by reacting toluene with nitric acid in the presence of sulphuric acid.
The advantage of TNT is that it is not sensitive to shocks and so can be handled without risk of accidental explosion. It can even be burned without exploding.
TNT has a low melting point (about 80°C), so it can be melted with steam and poured into the casings of gun shells.
 Connecting the detonator to an explosive charge.
Oxygen
Hydrogen
Carbon
Detonators
Most high explosives can only be detonated with the shock from another explosive.
This is why most explosive devices have a main explosive and a detonator. The detonator, or blasting cap, contains small amounts
of more sensitive explosive to set off a larger reaction.
There are several common detonating explosives, such as PETN (pentaerythrite tetranitrate) used in blasting caps. RDX (cyclotrimethylenetrinitramine) produces the highest energy yield and detonation pressure of any common explosive. Mixtures of RDX with plastic materials make “plastic explosive”. Ammonium nitrate explodes with a blast that is less violent and sudden than many other explosions. This is used to move an obstacle rather than to shatter it. Amatol (ammonium nitrite and TNT) is used as a blasting charge.
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