(hīdrŏl'ĭsĭs), chemical reaction of a compound with water, usually resulting in the formation of one or more new compounds. The most common hydrolysis occurs when a salt of a weak acid or weak base (or both) is dissolved in water. Water ionizes into negative hydroxyl ions (OH − ) and positive hydrogen ions (H + ), which become hydrated to form positive hydronium ions (H 3 O + ). The salt also breaks up into positive and negative ions. For example, when sodium acetate is dissolved in water it readily dissociates into sodium and acetate ions. Because sodium hydroxide is a strong base, the sodium ions react only slightly with the hydroxyl ions already present in the water to form sodium hydroxide molecules. Acetic acid is a weak acid, so the acetate ions react readily with the hydrogen ions present in the water to form neutral acetic acid molecules. The net result of these reactions is a relative excess of hydroxyl ions, causing an alkaline solution. A chemical reaction has actually taken…