What is the primary product of dehydrating alcohols with excess concentrated sulfuric acid?

The primary product of dehydrating alcohols with excess concentrated sulfuric acid is alkenes. During this dehydration process, the concentrated sulfuric acid acts as a catalyst, promoting the elimination reaction where water is removed from the alcohol molecule. As a result, the hydroxyl group (-OH) from the alcohol and a hydrogen atom from an adjacent carbon are eliminated, leading to the formation of a double bond between the carbon atoms, which characterizes alkenes.

This reaction is a typical example of dehydration, where alcohols lose water to form alkenes, particularly at higher temperatures, and when excess concentrated sulfuric acid is used, the reaction is driven towards the production of the alkene. Furthermore, the formation of different alkenes can occur depending on the structure of the starting alcohol and the conditions applied, but the overall primary result is the generation of alkenes from alcohols under these conditions.