Knowledge requirements:
(1) the synthetic equation, showing the molar relations of reagents and products
(2) molecular weight of reagents and products
(3) accurate weight of starting reagent
(4) accurate weight of end product
theoretical yield in grams =
= (moles of limiting reagent) * (molar ratio of product to reagent) * (molecular weight of product)
actual yield =
= weight of product in grams
percentage yield =
= (actual yield in grams) * 100% / (theoretical yield in grams)
Interpretation:
• The higher the yield, the more efficient the synthesis, with less waste.
• Very few reactions give yields of 100%.
• The yield may be falsely elevated if the product is not completely dried.