Solid aluminum and gaseous oxygen read in a combination reaction to produce aluminum oxide. 4Al (s) + 3O_2 (g) rightarrow 2Al_2O_3 (s) The maximum amount of Al_2O_3 that can be produced from 2.5 g of Al and 2.5 g of O_2 is g. 9.4 7.4 5.3 5.0 4.7

4.7 g. Option 5 is the right one.

Explanation:

4Al (s) + 3O₂ (g) ⇄ 2Al₂O₃ (s)

We convert the mass of reactants to moles, in order to determine the limiting.

2.5 g Al / 26.98 g/mol → 0.092 moles of Al

2.5 g O₂ / 32g/mol → 0.078 moles of O₂

Ratio is 4:3. 4 moles of Al react with 3 moles of O₂

Then, 0.092 moles of O₂ would react with (0.092. 3) / 4 = 0.069 moles O₂

We have 0.078 moles of O₂ and we need 0.069 moles, the oxygen is the limiting in excess. Therefore the Al is the limiting reactant.

Ratio is 4:2. 4 moles of Al, can produce 2 moles of Al₂O₃

Then, 0.092 moles of Al would produce (0.092.2) / 4 = 0.046 moles

If we convert the moles to mass, we find the anwer:

0.046 mol. 101.96 g/mol = 4.69 g