posted by lolo .
1) to the nearest gram, what is the molar mass of Al2O3?
when this reaction is reversed
what substance acts as an acid? what substance acts as a base ?
Tell me what your problem is with these questions. #1 is simply adding the atomic masses from the periodic table. #2 is knowing the Bronsted-Lowry theory of acids/bases. By the way, you omitted the + sign from the hydronium ion, H3O^+.