Limiting Reactant

Question

If 0.22 mol Ca is allowed to react with 0.13 mol of Oxygen. What is the limiting reactant?

Answer 1

Answer 2

Calcium + oxygen can be written as Ca + O₂

The product is CaO

So the balanced chemical reaction equation is:

2Ca + O₂ → 2CaO

Notice that this chemical reaction equation says that it takes 2 moles of calcium to react with 1 mole of oxygen. You are given 0.22 moles of calcium and 0.13 moles of oxygen. Can you see that you have more oxygen than is needed to go with the 0.22 moles of calcium? (it would only take 0.11 moles of oxygen to fully react with the 0.22 moles of calcium)

So, consequently, it is the amount of calcium that is limiting the reaction so we say that calcium is the limiting reactant.