WHAT IS THE MAJOR PRODUCT OF DEHYDRATION OF AN ALCOHOL?
An alkene.
It could be an alkene as DrBob indicated or an ether depending on experimental conditions such as temperature.
The major product of the dehydration of an alcohol is an alkene. To understand why, let's break it down step by step.
In the process of dehydration, an alcohol molecule loses a water molecule (H2O) to form an alkene. This reaction is typically carried out under acidic conditions, which means that an acid (such as sulfuric acid, phosphoric acid, or hydrochloric acid) is present.
Let's take the example of the dehydration of ethanol (CH3CH2OH).
1. First, the acidic conditions promote the protonation (addition of a hydrogen ion) of the alcohol molecule, resulting in the formation of an oxonium ion:
CH3CH2OH + H+ -> CH3CH2OH2+
2. Next, one of the hydrogen atoms attached to the carbon adjacent to the hydroxyl group (OH) is removed, along with the OH group itself, forming a water molecule:
CH3CH2OH2+ -> CH3CH=CH2 + H2O
3. This elimination step results in the formation of ethene (C2H4), which is the major product of the dehydration of ethanol.
In general, the dehydration of alcohols occurs through an E1 or E2 mechanism, where E stands for an elimination reaction. The exact mechanism depends on factors such as the type of alcohol, the presence of other functional groups, and the reaction conditions.
So, to summarize, the major product of the dehydration of an alcohol is an alkene.