Ethene is produced from ethanol by:
Dehydration.
Dehydration is the process of removing water from a compound. In the case of ethanol, the process of dehydration involves removing a molecule of water (H2O) from two molecules of ethanol (C2H5OH) to form one molecule of ethene (C2H4). The reaction is typically carried out using a catalyst, such as concentrated sulfuric acid or aluminum oxide.
The chemical equation for the reaction of ethanol to produce ethene by dehydration is:
C2H5OH → C2H4 + H2O
Therefore, the correct answer is "dehydration" - ethanol is converted to ethene by removing a molecule of water through the process of dehydration. The other options - decomposition, hydrolysis, and ozonolysis - do not accurately describe the process of producing ethene from ethanol.