Actual Yield and Percentage Yield
Remember
how to calculate “How much CO2 and H2O is
formed (in g) when 3 g of CH4 react with 5 g of O2?
How much of each reactant is left?” The answer is “1.25 g of
CO2, 3.4375 g of CO2 and 2.8125 g of H2O.”
We came up with these values from the limiting reagent lesson. If the reaction went 100% to completion (no more O2 left), then this is what would be created (these values are the theoretical yields, since they are only produced under the theory that the reaction would go to completion). But often, reactions don't go all the way. If we only consumed HALF the oxygen available, then we'd only create HALF these amounts of products (and only consume half the amount of CO2 as if the reaction went to completion). The amounts actually produced are called the actual (or experimental) yield. How close the reaction got to completion (as a percentage) is called the percentage yield.
We came up with these values from the limiting reagent lesson. If the reaction went 100% to completion (no more O2 left), then this is what would be created (these values are the theoretical yields, since they are only produced under the theory that the reaction would go to completion). But often, reactions don't go all the way. If we only consumed HALF the oxygen available, then we'd only create HALF these amounts of products (and only consume half the amount of CO2 as if the reaction went to completion). The amounts actually produced are called the actual (or experimental) yield. How close the reaction got to completion (as a percentage) is called the percentage yield.
Sample Question
Q:
Let's say that only 1 g of water was collected. What is the
percentage yield of the reaction?
A:
A:
