Calcium hydroxide
Calcium hydroxide (traditionally called slaked lime) is an inorganic compound with the chemical formula Ca(OH). It is a colorless crystal or white powder and is obtained when calcium oxide (called "lime" or "quicklime") is mixed, or slaked with water. It has many names including hydrated lime, caustic lime, builders' lime, slack lime, cal, or pickling lime. Calcium hydroxide is used in many applications, including food preparation, where it has been identified as E number E526. Limewater is the common name for a saturated solution of calcium hydroxide.
Hydron (chemistry)
In chemistry, a hydron is the general name for a cationic form of atomic hydrogen, represented with the symbol . However, this term is avoided and instead "proton" is used, which strictly speaking refers to the cation of protium, the most common isotope of hydrogen. The term "hydron" includes cations of hydrogen regardless of their isotopic composition: thus it refers collectively to protons (H) for the protium isotope, deuterons (H or D) for the deuterium isotope, and tritons (H or T) for the tritium isotope. Unlike most other ions, the hydron consists only of a bare atomic nucleus.