You're describing the thermite reaction, a very exothermic process! Here's how to figure out the moles of aluminum oxide formed:

1. Balanced Equation

The reaction is already balanced:

Fe₂O₃ + 2Al → Al₂O₃ + 2Fe

2. Mole Ratios

The balanced equation tells us the following mole ratios:

* 1 mole of Fe₂O₃ reacts with 2 moles of Al

* 1 mole of Fe₂O₃ produces 1 mole of Al₂O₃

* 2 moles of Al produce 1 mole of Al₂O₃

3. Information Needed

To determine the moles of Al₂O₃ formed, you need to know either:

* The moles of Fe₂O₃ used: If you know how many moles of Fe₂O₃ reacted, you'll get the same number of moles of Al₂O₃ produced.

* The moles of Al used: If you know how many moles of Al reacted, you can use the 2:1 mole ratio (Al to Al₂O₃) to calculate the moles of Al₂O₃ produced.

Example

Let's say you used 0.5 moles of Fe₂O₃. Since the mole ratio is 1:1 (Fe₂O₃ to Al₂O₃), you would produce 0.5 moles of Al₂O₃.

Let me know if you have the moles of either reactant, and I can calculate the moles of Al₂O₃ formed!