Back to Chapter 09 · The Stoichiometry Challenge
Which reactant runs out first?
The reaction ratio decides what runs out. Track supplies and product as the inventory changes.
Schematic teaching diagram · labels and text explain each state.
Read the sequence
- Enter the starting amounts. Divide Al by 2 and Cl₂ by 3 to compare how many reaction batches each supply can support.
- Advance the inventory. For every 2 mol Al consumed, 3 mol Cl₂ are consumed and 2 mol AlCl₃ are produced.
- The first supply to reach zero limits the product. Equal starting mole amounts do not mean neither reactant is limiting.
- Change one starting amount and replay. Compare the predicted product with the leftover reactant.
About this model. This is stoichiometric bookkeeping, not a molecular reaction mechanism or a laboratory demonstration. It assumes complete consumption of the limiting reactant and no competing reactions.