Limiting Reactant Determination

⚖️ Limiting Reactant Rescue Plan

🧪 Key Idea: The limiting reactant is the reactant that gets used up first — it limits how much product is formed.

✅ Step 1: Convert everything to moles. Step 2: Divide by coefficients. Step 3: The smaller answer = the limiter!

🔥 Top Mistakes to Avoid

• Comparing grams directly instead of converting to moles
• Forgetting to divide by the balanced equation coefficients
• Using excess reactant as the limiting one

🧠 Mini Check

If 5 mol of H₂ reacts with 2 mol of O₂ in: 2 H₂ + O₂ → 2 H₂O, which is limiting?

⚡ One Line Trick:

Convert → Divide → Compare. The one that gives the least product is limiting. Always.

🧠 Practice Drill

What mass of water is formed when 4.0 g of H₂ reacts with 32.0 g of O₂?

✏️ Tip: Always use mole ratio first. Limiter = least product possible.