Potassium in 1809, Ludwig Wilhelm Gilbert proposed the name "Kalium" for Davy's "potassium". In 1814, the Swedish chemist Berzelius advocated the name "kalium" for potassium, with the chemical symbol "K". The English and French speaking countries adopted Davy and Gay-Lussac/Thénard's name Potassium, while the Germanic countries adopted Gilbert/Klaproth's name Kalium. The "Gold Book" of the International Union of Physical and Applied Chemistry has designated the official chemical symbol as K. Potassium is the second least dense metal after lithium. It is a soft solid with a low melting point, and can be easily cut with a knife. Freshly cut potassium is
Potassium hypochlorite Potassium hypochlorite Potassium hypochlorite (chemical formula KClO) is the potassium salt of hypochlorous acid. It is used in variable concentrations, often diluted in water solution. It has a light grey color and a strong chlorine smell. It can be used as a disinfectant. Potassium hypochlorite is produced by the reaction of chlorine with a solution of potassium hydroxide: This is the traditional method, first used by Claude Louis Berthollet in 1789. Another production method is electrolysis of potassium chloride solution. With both methods, the reaction mixture must be kept cold to prevent formation of potassium chlorate. Potassium hypochlorite is used