Hydration reaction

In organic chemistry, a hydration reaction is a chemical reaction in which water is added to an unsaturated substrate. Usually, the substrate is an alkene or an alkyne.

Quotes

 * Water adds to alkenes to yield alcohols, a process called hydration.The reaction takes place on treatment of the alkene with water and a strong acid catalyst, such as H2SO4, by a mechanism similar to that of HX addition. … Acid-catalyzed alkene hydration is particularly suited to large-scale industrial procedures, and approximately 300,000 tons of ethanol is manufactured each year in the United States by hydration of ethylene. The reaction is of little value in the typical laboratory, however, because it requires high temperatures— 250 °C in the case of ethylene—and strongly acidic conditions.
 * John McMurry, Organic Chemistry 8th ed. (2012), Ch. 8 : Alkenes: Reactions and Synthesis