2Limiting Reactant Limiting Reagent The reactant that is totally used up during the chemical reactionLimits the amount of product produced
3Excess 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
4What is the limiting reactant? What are the excess reactants?
5Steps 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
61 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
7How 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
8Ba(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