Thermite reaction
When ignited by a glycerin/permanganate reaction, an aluminum/iron oxide mixture reacts vigorously and spectacularly, producing molten iron and aluminum oxide.
aluminum
Reaction of aluminum with iodine
Powdered aluminum and powdered iodine are mixed together. Adding drops of water to the mixture initiates a reaction.
Aluminum iodine reaction
Powdered aluminum and solid iodine are mixed and no reaction is observed. Adding water to the mixture initiates a reaction.