Actual & Theoretical Yield
- Yield is the term used to describe the amount of product you get from a reaction.
- In practice, you never get 100% yield in a chemical process for several reasons.
- These include:
- Some reactants may be left behind in the equipment.
- The reaction may be reversible and in these reactions a high yield is never plausible as the products are continually turning back into the reactants.
- Some product may also be lost during separation stages such as filtration or distillation.
- There may be a side reaction occurring where a substance reacts with a gas in the air or an impurity in one of the reactants.
- Products can also be lost during transfer from one container to another.
- The actual yield is the recorded amount of product obtained.
- The theoretical yield is the amount of product that would be obtained under perfect practical and chemical conditions.
- It is calculated from the balanced equation and reacting masses.
- The percentage yield compares the actual yield to the theoretical yield.
- For economical reasons, the objective of every chemical producing company is to have as high a percentage yield as possible to increase profits and reduce costs and waste.
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Morgan’s passion for the Periodic Table begun on his 10th birthday when he received his first Chemistry set. After studying the subject at university he went on to become a fully fledged Chemistry teacher, and now works in an international school in Madrid! In his spare time he helps create our fantastic resources to help you ace your exams.