Potassium Hydroxide Solutions

Potassium hydroxide (KOH) was discovered by British scientist Sir Humphry Davy in 1807. He used electrolysis to isolate KOH. He later also used this method to isolate sodium, calcium, strontium, barium and other hydroxides. KOH is a strong base with a high pKb. Its behavior is similar to that of sodium hydroxide. KOH is mostly used industrially in soaps/cosmetics, fertilizers, batteries, and cleaners.

KOH standard solutions are normally standardized with hydrochloric acid normality solutions, as well as directly with KHP (potassium hydrogen phthalate) primary standard. Typically, phenolphthalein indicator is used, although other suitable ones include methyl orange, bromocresol green, methyl red, and thymolphthalein.

Exaxol offers different percent solutions of KOH, the strongest being 45% w/w (concentrated). Also available are percent/volume solutions (45% w/v, for example). Standard normality solutions range from weak to strong concentrations, with the most used are 0.1N to 1N. Weaker solutions (like sodium hydroxide) tend to absorb atmospheric carbon dioxide over time, and this will affect the endpoint of a titration. Usually, this is a minor effect, and the endpoint color should hold for at least 30 seconds.

Exaxol KOH solutions are made/tested in our ISO 17025 Accredited laboratory.  We offer both aqueous as well as methanolic standardized solutions.