Atom economy and yield Flashcards
Actual yield
Actual mass of a product in a chemical reaction
Theoretical yield
Maximum possible mass of a product
If every single reactant reacted
Percentage yield
Measure of how much product is actually made in a reaction
How to find percentage yield?
Actual yield
————————- x 100
Theoretical yield
Why is it not always possible to get the theoretical yield?
Reaction may not be completed because it’s reversible
Some of the product may be lost when separated from mixture
Some of the reactants may react in unexpected ways
Atom economy
A measure of how many reactant atoms form a desirable product
Compared to forming waste products
How to calculate atom economy?
Total Mr of desired product
——————————————- x 100
Total Mr of all reactants
How to find the theoretical yield
Mass of limiting reactant
————————————————
Sum of Ar/Mr of limiting reactant
When calculating atom economy, what changes about the Mr?
We include the big number at the start of the compound - unlike when using the Mr to calculate the moles where we don’t include it
Can you have an atom economy of over 100%?
NO because that means we are creating atoms which isn’t possible.
Why do we use atom economy?
Minimise the production of unwanted products and save money
Being sustainable by not wasting resources
