Chemical Reaction Yield
Compute a chemical reaction's yield, Y = (actual mass obtained / theoretical mass)·100%, comparing what was actually produced with the maximum predicted by stoichiometry. Real reactions rarely reach 100%: there are incomplete reactions, side reactions, purification losses. Yield is the efficiency indicator that separates paper chemistry from lab and industrial chemistry. Enter the actual mass obtained and the theoretical mass.
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Chemical reaction yield
The yield R = (actual mass / theoretical mass) · 100% is the efficiency gauge of any chemical synthesis. The theoretical mass is the maximum that stoichiometry allows — computed from the limiting reagent, assuming a perfect and complete reaction. The actual mass is what really gets isolated in the flask. And real life is unkind: incomplete reactions (which stall at equilibrium), side reactions that divert reagent into by-products, losses during purification (filtration, recrystallisation, extraction), and even plain handling all drag the number down. Yields of 70–90% count as good on the bench; multi-step syntheses multiply the losses (10 steps at 90% each leave a mere ~35% overall!), which is the nightmare of complex drug synthesis. In industry every percentage point of yield, multiplied by tonnes of product, is worth a fortune — and separates a profitable process from an unviable one. Enter the actual mass obtained and the theoretical mass.
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The results provided by this tool are for general informational and educational purposes only and do not constitute professional, financial, medical, legal, tax or accounting advice. Always confirm important decisions with a qualified professional and official sources.