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Chemistry stoichiometry PerCENT YIELD. Calculators required Periodic table required. Percent Yield. When a reaction is performed, the amount of product that you collect in your lab equipment and measure is called actual yield .
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ChemistrystoichiometryPerCENT YIELD Calculators required Periodic table required
Percent Yield • When a reaction is performed, the amount of product that you collect in your lab equipment and measure is called actual yield. • Since we can now calculate the amount of product mathematically, we can compare our actual yield to what we “should have” gotten mathematically, or theoretical yield.
Actual Yield Theoretical Yield Percent Yield = x 100 Percent Yield • Percent yield is the ratio of theoretical yield (stoichiometry) to actual yield (experimental): • This percentage is almost always under 100%. Product is nearly always lost, if the stoichiometry is done correctly.
LONG SUMMATIVE Example lead (II) nitrate + potassium iodide. 1) What is the balanced equation, and what will be the precipitate?
LONG SUMMATIVE Example lead (II) nitrate + potassium iodide. 2) How much KI should we combine with 3 grams Pb(NO3)2? 3) How much PbI2 should we get at the end of the reaction? Pb(NO3)2(aq) + 2KI(aq) PbI2(s) + 2KNO3(aq)
LONG SUMMATIVE Example lead (II) nitrate + potassium iodide 4) What is the percent yield, if the actual yield is 4.00 g? Pb(NO3)2(aq) + 2KI(aq) PbI2(s) + 2KNO3(aq)