(chemistry) KMnO₄, the most readily available commercial permanganate; it is used as an oxidizing agent both in industry and in the analytical laboratory.

(inorganic chemistry) KNO₃, a naturally occurring salt, notably used as an ingredient of gunpowder; also used a food preservative and as an ingredient in toothpaste for sensitive gums; historically used in the production of nitric acid (HNO₃).

(chemistry) The potassium salt of nitrous acid, KNO₂.

(chemistry) The potassium salt of sorbic acid.

(chemistry) a salt, KI, formally derived from potassium hydroxide and hydriodic acid, used as an analytical reagent, in organic synthesis, and in the preparation of photosensitive emulsions and as a radioprotector to protect the thyroid.

(organic chemistry) The potassium salt of benzoic acid.

(inorganic chemistry) A yellowish brown solid, KNH₂, obtained by heating potassium in ammonia gas. It is most commonly used as a base to create a carbanion of an enolate.

(physics) An artificially produced radioactive isotope of potassium, ⁴³₁₉K, having a half-life of 22 hours; used in medicine as a tracer

(chemistry) A potassium salt of chromic acid, K₂Cr₂O₇; the orange crystals are soluble in water, and it is used as an oxidizing agent and in photography.

(inorganic chemistry) The potassium salt of hydrocyanic acid, KCN; the colourless crystals are soluble in water, and it is extremely poisonous, and is used in electroplating, the extraction of gold and silver from their ores, and in photography.