Final answer:
The major product from the dehydration of ethanol is ethene, and the primary product from the dehydration of 2-methyl-2-propanol is 2-methylpropene.
Step-by-step explanation:
The major product expected from the dehydration of ethanol (C2H5OH) when heated in sulfuric or phosphoric acid is ethene (a.k.a. ethylene). This is because under the conditions of excess concentrated sulfuric acid at 180 degrees celsius, ethanol dehydrates to form ethene and a side product of a water molecule.
When 2-methyl-2-propanol is subjected to dehydration in the presence of sulfuric acid, the primary product formed is 2-Methylpropene. This is due to the alcohol undergoing a dehydration reaction where a water molecule is eliminated, resulting in the formation of the alkene. Dehydration of alcohols to form alkenes is a common chemical transformation.