Step 1: Understanding the Concept:
Atom economy is a measure of the efficiency of a chemical reaction in terms of how many atoms from the reactants end up in the desired final product.
Step 3: Detailed Explanation:
High atom economy means that most of the reactant atoms are incorporated into the useful product, minimizing waste.
The formula is:
\[ % \text{ Atom Economy} = \frac{\text{Molecular mass of the desired product}}{\text{Total molecular mass of all reactants used in the balanced equation}} \times 100 \]
Step 4: Final Answer:
The % atom economy is the ratio of product mass to total reactant mass, expressed as a percentage.