1. Percentage Yields

2. Frequently part of the organic practical question

3. Actual Yield Amount of product you get in the reaction
Sometimes this is given as a density and a volume
Mass = density * volume
23 ml of ethanol [density 0.8g/cm3]
23 * 0.8 = 18.4 g

4. % Yield = Actual Yield * 100
Theoretical Yield

5. Theoretical Yield
is the amount you would get if all of the limiting reactant became products.
This is calculated using the balanced equation

6. This rarely happens; in many reactions yields are low, especially in organic reactions