Chemistry question?

Question

what is the limiting reagent for the reaction below given that you strat with 10.0 grams of Al and 19.0 grams of O2? Reaction: 4Al + 3O2>>2AlO3

Answer 1

if you look at the molecular weight , you need 108g of al for 96g of O2

So O2 is the limiting product

Answer 2

4Al(s) + 3O2(g) ==> 2Al2O3
molar mass Al = 26.98/mol
molar mass O2 = 32.00g/mol

Al:
10.0g / 26.98g/mol = 0.371mol x 2/4 = 0.186mol Al2O3
O2:
19.0g / 32.00g/mol = 0.594mol x 2/3 = 0.396mol Al2O3

the limiting reagent is aluminum since less product is formed