Atom Economy: Aspirin Synthesis
In the synthesis of aspirin (180.16 g/mol) from salicylic acid and acetic anhydride (total reactants 198.17 g/mol), the atom economy is approximately 91%.
How to use this tool
- Enter molar mass of desired product, stoichiometric coefficient of product and total molar mass of all reactants (sum of m×coeff) in the fields above.
- Results update instantly as you type — or click Calculate.
- Read your atom economy and the full breakdown beneath it.
Aspirin synthesis via acetylation has a good atom economy of about 91%, with only acetic acid as a by-product.
Frequently asked questions
- What is atom economy used for?
- It was introduced by Barry Trost (1991) as a measure of synthetic efficiency. High atom economy reactions waste fewer atoms and generate less chemical waste, making them preferable in green chemistry and industrial synthesis.
- What is the difference between atom economy and percent yield?
- Percent yield measures how much of the theoretical product you actually collected. Atom economy measures how much of the reactant mass ends up in the desired product regardless of yield. A reaction can have 100% yield but low atom economy if most reactant atoms end up in by-products.