Year 11 - Science
Percentage yield and atom economy (RAM 1 d.p.)
Industrial chemistry
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This pupil-friendly study guide includes a unit summary, clear notes, common mistakes, and quick questions with answers.
Unit Summary
This unit covers corrosion, prevention methods, and properties of alloys, ceramics, polymers, and metals. It explores industrial processes like the Haber process, fertiliser production, reaction rates, yields, atom economy, and the trade-offs involving conditions and equilibrium.
Lesson Summary
You will learn to perform calculations related to various aspects of industrial processes, and explain decision-making about the chosen reaction pathways in those processes.
Key Notes
- In an ideal chemical reaction, all atoms in the reactants would end up in useful products, with no waste.
- The theoretical yield of a chemical reaction can be calculated from the reaction equation alone.
- The percentage yield shows how actual yield compares with theoretical yield.
- Atom economy is a measure of the efficiency with which a reaction uses its reactants.
- Many factors will be considered when choosing a reaction pathway.
Vocabulary To Learn
- theoretical yield: is the maximum calculated mass of product expected to form from a given mass of reactants
- actual yield: is the actual amount of product obtained from a chemical reaction
- percentage yield: is the actual yield (mass of product obtained) divided by the theoretical yield (maximum mass of product possible), as a percentage
- atom economy: is the percentage, by relative mass, of reactants that are converted into useful products
- useful product: is a chemical product that is desired or valuable
Common Mistakes To Avoid
- Students often confuse percentage yield with atom economy, thinking both measure the same efficiency aspect.
3 Quick Questions (With Answers)
1. Explain the scientific idea in this lesson using two key points.
In an ideal chemical reaction, all atoms in the reactants would end up in useful products, with no waste. The theoretical yield of a chemical reaction can be calculated from the reaction equation alone.
2. Define this scientific word and use it in context. 'theoretical yield'
is the maximum calculated mass of product expected to form from a given mass of reactants. Include the word in a full scientific explanation, not as a single label.
3. Correct this common scientific misunderstanding.
Mistake: Students often confuse percentage yield with atom economy, thinking both measure the same efficiency aspect. Correction: Clarify that percentage yield measures actual vs. theoretical product amount, while atom economy measures reactants' mass converted to desired product.
More Lessons In This Unit
- Ammonia: NPK fertiliser production and other applications Study Guide
- Chemical equilibrium Study Guide
- Comparing materials and their properties Study Guide
- Corrosion and its prevention Study Guide
- Corrosion and its prevention: including half equations Study Guide
- Equilibrium: balance between rate, safety, environment and economics Study Guide
- Factors affecting equilibrium Study Guide
- Industrial equilibria: Contact Process Study Guide
- Industrial equilibria: Haber Process Study Guide
- Introduction to reversible chemical reactions Study Guide
- Making ammonia Study Guide
- NPK fertilisers, agriculture and other applications Study Guide
- Percentage yield and atom economy Study Guide
- Transition metals Study Guide
- Transition metals: physical and chemical properties Study Guide
- Transition metals: properties and uses Study Guide
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