Answer:
The answer to your question is: x = 0.185 mol of Al2O3
Explanation:
Data
10 g of Al and 19 grams of O2
Reaction: 4Al + 3O2 → 2Al2O3
4(27) 3(32) 2 ( 102)
108g 96g 204g
Limiting reactant
108g Al ------------------ 96g O2
10 g ----------------- x
x = (10 x 96) / 108 = 8.9 g of O2
Then limiting reactant is Al
So
108 g of Al ---------------------- 204 g of Al2O3
10 g ---------------------- x
x = (10 x 204) / 108 = 18.8 g of Al2O3
102 g of Al2O3 ----------------- 1 mol
18.8 ----------------- x
x = 0.185 mol of Al2O3