Final answer:
The question seemingly refers to an oxymercuration-demercuration reaction, but the alkene substrate is missing. The typical major product of such a reaction with an alkene, Hg(OAc)2, and H2O would be an alcohol.
Step-by-step explanation:
The student is referring to a reaction involving Hg(OAc)2 and H2O. Specifically, this is a reaction known as oxymercuration-demercuration, which typically hydrates alkenes to form alcohols
However, the question as it stands is incomplete because it does not specify the organic substrate (the alkene) that reacts with Hg(OAc)2 and H2O. The expected major product in an oxymercuration-demercuration reaction would generically be an alcohol.