"Keep your powder dry"
Solubility of compounds in water

Gunpowder is a mixture of carbon, potassium nitrate and sulfur. When ignited the ingredients undergo a powerful chemical reaction that produces gaseous products and releases a great deal of heat. However, discovered in 1245 by Friar Roger Bacon, gunpowder must be kept dry. Hence the term "Keep your powder dry".
Water molecules dissolve soluble substances. Once dissolved the molecules or particles are not in a position to react together and cause a reaction to take place. Click to see a Flash animation of the property of water to dissolve substances. The source of this animation is unknown. If copyright is infringed, notify the writer to remove it immediately.
Guncotton or nitrocellulose, just like gunpowder, was used to fire cannon balls. However it can be stored safely in water without deteriorating. When needed, it is taken out of the water and dried. Click to see the burning of gun cotton when dry.
Gunpowder is a
Guncotton is a
Potassium nitrate is a salt and is sometimes referred to as saltpeter. View the animation of how salt dissolves and suggest a reason why wet gunpowder is useless, even after drying.
Why can guncotton be stored safely underwater but gunpowder can not?