Section 1 of 5Percentage Yield
Core Concept
- Core Concept Fundamental principles, definitions, and physical or chemical laws governing this topic.
Mechanism & Behavior
- Mechanism & Behavior Key interactions, structural properties, and process dynamics observed in experiments.
Exam Applications
- Exam Applications Quantitative relationships, key formulas, and criteria required by specification mark schemes.
Section 2 of 5Theoretical Masses of Products
1
Obtaining calculated masses Higher tier only We can obtain theoretical masses of products using a balanced equation and a given mass of reactant How to calculate theoretical mass The process is as follows: 1
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Write out the balanced equation for the reaction(if not already given in the question) 2
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Convert the given mass of reactant(s) into moles, by dividing the masses by the molar masses 3
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Use the coefficients(multipliers) in the equation to deduce the number of moles of the product(s) 4
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Convert the moles of product into mass by multiplying by the molar mass The following example illustrates the process: Worked Example In an experiment to displace copper from copper(II)sulfate, 6.5g of zinc was added to a solution of copper(II)sulfate
Section 3 of 5Calculating Atom Economy
Calculating Atom Economy
The reaction is as follows
- The reaction is as follows CH (g) + H O (g) → CO (g) + 3H (g) Calculate the atom economy of this reaction
You
- You can calculate atom economy using either the total M of all products or the total M of all reactants, as long as the equation is fully balanced
These values will be the same
- These values will be the same Atom economy = total Mr of desired product total Mr of all reactants × 100 Atom economy = total Mr of desired product total Mr of all products × 100 Just make sure you’re using the M of the desired product in the numerator
Section 4 of 5Choosing a Reaction Pathway
Core Concept
- Core Concept Fundamental principles, definitions, and physical or chemical laws governing this topic.
Mechanism & Behavior
- Mechanism & Behavior Key interactions, structural properties, and process dynamics observed in experiments.
Exam Applications
- Exam Applications Quantitative relationships, key formulas, and criteria required by specification mark schemes.
Section 5 of 5Exam Checklist & Tips
Specification Mastery Checklist
- Key Definitions Ensure precise recall of terms and units as required by examination mark schemes.
- Equations & Formulas Double-check balanced state symbols, subscripts, and SI unit conversions.
- Common Misconceptions Verify experimental conditions, controls, and comparative trends across groups.