2 Limiting Reactant Limiting Reagent The reactant that is totally used up during the chemical reactionLimits the amount of product produced
3 Excess Reactant Excess Reagent The reactant present in a quantity that is greater than what is needed to react with the limiting reactantRemains after the limiting reactant has been used up
4 What is the limiting reactant? What are the excess reactants?
5 Steps Balance the equation Identify the givens (there are 2!) Identify what you want to findUse stoichiometry to solveThe reactant with a smaller amount of product produced is the limiting reactantThe other reactant is in excess
6 1 MgBr2 + 2 AgNO3 2 AgBr + 1 Mg(NO3)2 How many grams of silver bromide (AgBr) can be formed when solutions containing 50.0 g of MgBr2 and g of AgNO3 are mixed together? What is the limiting reactant? What is in excess?1 MgBr AgNO AgBr + 1 Mg(NO3)250.0 g MgBr2 1 mol MgBr mol AgBr g AgBrg MgBr mol MgBr mol AgBr= 102 g AgBr100.0 g AgNO3 1 mol AgNO mol AgBr g AgBrg AgNO mol AgNO mol AgBr= g AgBrLimiting Reactant (LR) = MgBr2Excess Reactant (ER) = AgNO3
7 How many grams of hydrogen chloride can be produced from 1 How many grams of hydrogen chloride can be produced from 1.00 g of hydrogen and 55.0 g of chlorine? What is the limiting reactant? What is in excess?H2 + Cl HCl1.00 g H mol H mol HCl g HCl2.02 g H mol H mol HCl= 36.1 g HCl55.0 g Cl mol Cl mol HCl g HCl70.90 g Cl mol Cl mol HCl= 56.6 g HClLimiting Reactant (LR) = H2Excess Reactant (ER) = Cl2
8 Ba(NO3)2 + Na2SO4 BaSO4 + NaNO3 How many grams of barium sulfate (BaSO4) will be formed from g of barium nitrate (Ba(NO3)2) and g of sodium sulfate (Na2SO4)? What is the limiting reactant? What is in excess?Ba(NO3)2 + Na2SO BaSO4 + NaNO3200.0 g Ba(NO3)2 1 mol Ba(NO3) mol BaSO g BaSO4g Ba(NO3)2 1 mol Ba(NO3)2 1 mol BaSO4= g BaSO4150.0 g Na2SO4 1 mol Na2SO mol BaSO g BaSO4g Na2SO mol AgNO mol BaSO4= g BaSO4Limiting Reactant (LR) = Ba(NO3)2Excess Reactant (ER) = Na2SO4