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Percentage Yield. Identify the limiting reactant and calculate the mass of a product, given the reaction equation and reactant data. Include: theoretical yield , experimental yield Additional KEY Terms Actual yield.
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Identify the limiting reactantand calculate the mass of a product, given the reaction equation and reactant data. • Include: theoretical yield, experimental yield • Additional KEY Terms • Actual yield
Theoretical yield: amounts of product calculated from the limiting reagent. Actual yield: amount produced during the conducted experiment. Percentage yield: ratio of actual to theoretical yield expressed in percentage. actual yield x 100 percent yield = theoretical yield
Reactions are influenced by "external" factors which effect the amount of yield produced: • Concentration • State (s, l, g, aq) • Temperature • Pressure (of gas reactants) • Human error Poor recovery Impurities in reactants Miscalculation A side reaction occurs
2 KClO3 2 KCl + 3 O2 5.00 g of KClO3 is heated and decomposes to yield 1.78 g of O2. What is the % yield? 5.00 g KClO3 1 mole 3 mole O2 32.0 g O2 1 mole O2 2 mole KClO3 122.5 g = 1.96 g O2 actual yield 1.78 g x 100 90.8 % percent yield = 1.96 g theoretical yield
How much O2 would be produced if the percentage yield was 78.5%? Ac. yield 1.96 g x 100 78.5 % = % yield = Th. yield 1.53 g = Ac. yield
What is the % yield if 58 g H2O are produced by combining 60.0 g O2 and 7.0 g H2? O2(g) + 2 H2 (g) 2 H2O (g) 60.0 g O2 1 mole O2 2 mole H2 2.0 g H2 1 mole O2 1 mole H2 32.0 g O2 = 7.5 g H2 H2 - limiting reactant, O2 - excess reactant
7.0 g H2 1 mole H2 2 mole H2O 18.0 g 2 mole H2 1 mole 2.0 g H2 = 63 g H2O produced actual yield 58 g x 100 92 % percent yield = theoretical yield 63 g
CAN YOU / HAVE YOU? • Identifythe limiting reactantand calculate the mass of a product, given the reaction equation and reactant data. • Include: theoretical yield, experimental yield • Additional KEY Terms • Actual yield