Presentation on theme: "Laboratory 08 LIMITING REACTANT LAB. Objectives 1.Understand mole-to-mole ratio in a balanced chemical reaction 2.Identify the limiting and excess reactant."— Presentation transcript:
Objectives 1.Understand mole-to-mole ratio in a balanced chemical reaction 2.Identify the limiting and excess reactant in a chemical reaction based on experimental observation 3.Conduct limiting reactant calculations to predict theoretical yield
Limiting Reagent: The reagent that is completely used up in a chemical reaction. Excess Reagent: Reagent not completely used up in a chemical reaction.
The Concept of Limiting Reactants Stoichiometric mixture N 2 (g) + 3H 2 (g) 2NH 3 (g)
Example: Find the limiting reagent when 1.22g O 2 reacts with 1.05g H 2 to produce H 2 O.
–Convert mass to moles: 0.038 mol O 2, 0.5 mol H 2 –Calculate H 2 moles necessary to react with O 2 : 0.076 mol H 2. –Compare 0.076 mol H 2 to actual mol of H 2 (0.5mol H 2 ), –Since 0.5 mol H 2 is more than 0.076 mol H 2, H 2 is the excess reagent and O 2 is the limiting reagent. 2H 2 (g) + O 2 (g) 2H 2 O (l)