Calcium hydroxide is an inorganic compound, commonly known as hydrated lime and slaked lime. It is a fine white powder at room temperature, slightly soluble in water. Its clear aqueous solution is commonly called clear lime water, and the emulsion suspension composed of water is called lime milk. The solubility decreased with the increase of temperature. It is insoluble in alcohol, soluble in ammonium salt and glycerin, and can react with acid to generate corresponding calcium salt.