What is produced when excess ammonia is used in the substitution reaction with ethanol?

When excess ammonia is used in a substitution reaction with ethanol, the primary product is amines. This reaction typically involves the nucleophilic substitution process where ammonia acts as a nucleophile, replacing a hydroxyl (-OH) group in ethanol. This results in the formation of an alkyl amine.

In this reaction, ethanol (which has the hydroxyl functional group) reacts with ammonia, where the ethanol loses the -OH group and is replaced by the -NH2 group from the ammonia. When there is excess ammonia, it enhances the likelihood that the reaction will fully convert ethanol to the corresponding amine, rather than forming other possible byproducts.

The other options, while related to various organic chemistry processes, do not accurately describe the product of this specific substitution reaction. Halogenoalkanes involve reactions where a halogen replaces a different functional group, alkenes are typically formed through elimination reactions rather than substitution, and aldehydes arise from oxidation processes rather than substitution with ammonia. Thus, the formation of amines represents the correct outcome of the reaction when excess ammonia is employed.