Answer:
Al³⁺
Step-by-step explanation:
Let's consider the following balanced reaction.
2 Al³⁺ + 3 O²⁻ ⇒ Al₂O₃
The theoretical molar ratio (TR) of Al³⁺ to O²⁻ is 2/3 = 0.66:1.
We have 0.15 moles of aluminum ions and 0.25 moles of oxide ions. The experimental molar ratio (ER) is 0.15/0.25 = 0.6:1.
Comparing the TR with the ER, we can establish that the limiting reactant is Al³⁺.