Synthesis

How do you calculate limiting reagent and yield?

Which reagent runs out, the theoretical yield, and what is left over. The relationship used is limiting = min(n / coeff) ; yield = limiting · coeff_p · MW_p.

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Worked example

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What you are given

Reactants: [{"name":"H2","coeff":"2","mass":"20.16","mw":"2.016"},{"name":"O2","coeff":"1","mass":"320","mw":"32"}]
Product coefficient: 2
Product MW (g/mol): 18.015

Formula: limiting = min(n / coeff) ; yield = limiting · coeff_p · MW_p

The working

Limiting: min(mmol / coeff) = H2 (5 mmol per unit coeff)
Theoretical yield: min ratio · product coeff · MW = 180.15 mg

Limiting reagent: H2. Theoretical yield 180.15 mg.

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