The conversion of ethylene to ethyl alcohol is known as

A hydration reaction is a chemical reaction that occurs when a material reacts with water. In organic chemistry, water is added to an unsaturated substrate, which is commonly an alkene or an alkyne. 

Ethanol can be changed to ethene by heating it with concentrated sulphuric acid and releasing water.

The three steps of the reaction are as follows:

a. An electrophilic attack on the hydronium ion occurs, pronating the ethene to create a carbocation.

b. In the second stage, the water molecule attacks the carbocation.

c. The ethanol is finally produced by deprotonation.