# How is the percent yield calculated?

Jul 18, 2018

Just to retire this question....

#### Explanation:

...usually we take the quotient...

"% yield"="moles of product"/"moles of limiting reactant"xx100%

And to find out the $\text{limiting reactant}$ we have to write the stoichiometric reaction that represents the synthesis of the product. For, say an esterification reaction in which the alcohol were present in excess...

$R C {O}_{2} H + R ' O H \stackrel{{H}^{+}}{\rightarrow} R C {O}_{2} R ' + {H}_{2} O$...

...we would assess the yield on the basis of...

"% yield"=n_"ester"/n_"parent acid"xx100%=??%..

Here product ester, and parent acid are present in a $1 : 1$ molar ratio...this ratio will not apply with other stoichiometries...