Atom Economy: A measure of the proportion of reactant atoms that become part of the desired product in a balanced chemical reaction.
Atom Economy in Industry
Atom Economy in Industry:
- Try to use reactions with a high atom economy.
- So they're not spending money producing waste or by-products.
- Reactions with a low atom economy may still be used if their waste can be sold or used elsewhere (gases, salts and acids can often be useful in other reactions).
Calculating Atom Economy
Calculating Atom Economy:
% atom economy = (mass of desired product / total mass of reactants) x 100
E.g. Ethanol can be produced by fermenting glucose: C6H12O6 >>> 2C2H5OH + 2CO2
Calculate the % atom economy for this reaction.
1. Calculate the total mass of the reactants (1 mole of glucose):
(6 x 12) + (12 x 1) + (6x16) = 180
2. Find the mass of the desired product (2 moles of ethanol):
2 x ((12 x 2) + (5 x 1) + 16 + 1) = 92
3. % atom economy = (92 / 180) x 100 = 51.1%