What is value of percent atom economy when reactants having sum of formula weight 78 u results in the…
What is value of percent atom economy when reactants having sum of formula weight 78 u results in the formation of a product with formula weight 65 u ?
$70 \%$
$78 \%$
$83 \%$
$65 \%$
Solution
$\begin{aligned} & \% \text { atom economy } \\ & =\frac{\text { Formula weight of the desired product }}{\text { Sum of formula weight of all the }} \times 100 \\ & \text { reactants used in the reaction } \\ & =\frac{65 \mathrm{u}}{78 \mathrm{u}} \times 100=83 \%\end{aligned}$