First a balanced reaction equation must be established:

→

Now if mass of aluminum = 145 g
the moles of aluminum = (MASS) ÷ (MOLAR MASS) = 145 g ÷ 30 g/mol
= 4.83 mols
Now the mole ratio of Al : O₂ based on the equation is 4 : 3
[
4Al +
3 O₂ → 2 Al₂O₃]
∴ if moles of Al = 4.83 moles
then moles of O₂ = (4.83 mol ÷ 4) × 3
=
3.63 mol (to 2 sig. fig.)
Thus it can be concluded that
3.63 moles of oxygen is needed to react completely with 145 g of aluminum.
Correct answer: B. Paleozoic. I took the test and it was right.
The answer is the first option, <span>∆G is positive.</span><span> </span><span>Endergonic reaction is a chemical reaction where the Gibbs free of energy is positive and there is abosrption of energy. It is a nonspontaneous reaction or unfavorable reaction.</span>
Answer:
c. iron I hope it helped.....
Ok buddy sorry buddy I just got