Chemical fertilizers
Glass, lenses
Matches, gun-powder
dietetic salt (KCl)

Potassium forms alloys with many metals, but only the alloy obtained with the sodium has some interest in the technology of nuclear reactors. The more important compounds, from the point of view of applications, are chloride, sulfate, nitrate, carbonate and hydroxide. The salts are used not only as constituents of fertilizers but also for other more specific goals. The sulfate is used as addictive of the gypsum to control its hardening speed and its resistance, the carbonate is used in the production of special glasses and in ceramics, and the potassium nitrate is used in the production of explosives. The potassium chloride, as well as the hydroxide, are the main sources to obtain other salts; the latter one is also used as industrial reagent for producing liquid soaps, as electrolyte in certain batteries and as absorbent of carbon dioxide and hydrogen sulfide.

Other less common salts are used in Medicine: the bromide as sedative, the potassium permanganate as bactericide, etc.