Editing Explosive (section)

===Hygroscopicity and water resistance===
The introduction of [[water]] into an explosive is highly undesirable since it reduces the sensitivity, strength, and velocity of detonation of the explosive. [[Hygroscopicity]] is a measure of a material's moisture-absorbing tendencies. Moisture affects explosives adversely by acting as an inert material that absorbs heat when vaporized, and by acting as a solvent medium that can cause undesired chemical reactions. Sensitivity, strength, and velocity of detonation are reduced by inert materials that reduce the continuity of the explosive mass. When the moisture content evaporates during detonation, cooling occurs, which reduces the temperature of reaction. Stability is also affected by the presence of moisture since moisture promotes decomposition of the explosive and, in addition, causes corrosion of the explosive's metal container.

Explosives considerably differ from one another as to their behavior in the presence of water. Gelatin dynamites containing nitroglycerine have a degree of water resistance. Explosives based on [[ammonium nitrate]] have little or no water resistance as ammonium nitrate is highly soluble in water and is hygroscopic.