Percentage Yield Flashcards
What is percentage yield ?
It gives information on the practical efficiency of a chemical reaction.
What do many chemical calculations assume ?
Many chemical calculations assume reactions produce a 100% yield
Why do no reactions produce a 100% yield?
The reaction doesn’t go to completion
Unwanted side reactions occur
Percentage yield calculation
Actual mass / theoretical mass x100
What can the values for actual and theories mass be
Moles or mass - the unit for both values must be the same though
Why is the amount made less than maximum theoritical mass ?
Reversible
Product lost or isolation
Other reactions take place
What does the production of many industrial chemicals require ? And what does this mean for the yield ?
The production of many industrial chemicals and pharmaceuticals require multi step reactions . As such the yield can be suprisingly low because the overall yield is dependant on each step of the process (there’s no link between atom economy and percentage yield )
