1. Percent Yield
Unit 8 Lesson 3

2. Percent Yield experimental yield % Yield = x 100 theoretical yield
In a laboratory setting, it is rare to produce as much product as you theoretically should.
Theoretical Yield - amount of product that should be obtained as predicted by stoichiometry (calculated)
Experimental Yield - amount of product actually obtained in an experiment (often smaller but sometimes bigger)
Percent yield is the opposite of percent error. Percent error is how far off the right answer you were. Percent yield is how much product you got.
This is the opposite of percent error. Percent error is how far off the right answer you were. Percent yield is how much product you got.
experimental yield
% Yield =
x 100
theoretical yield

3. Sample Problem
Determine the percent yield for the reaction if you calculated that g Al(OH)3 could be produced but only g Al(OH)3 is actually recovered during the experiment.

4. Sample Problem
You react 9.85 grams of CH4 with an unlimited supply of oxygen and make 14.5 grams of water. What was your percent yield?
Calculate Theoretical Yield
CH4 + O2  H2O + CO2
Balance! CH4 + 2O2  2H2O + CO2

5. Continued
Theoretical = 22.1 g H2O
Experimental = g H2O
65.6%