Mole Calculations
Use this landing page to move quickly between the key mole calculation revision pages for Topic 5. Each card links to a focused page covering relative masses, mole equations, reacting masses, percentage yield and atom economy.
Choose a Mole Calculations Page
Mole calculations connect the symbolic equation to measurable quantities in the laboratory. These pages build from comparing masses and using the mole equation through to reacting mass calculations, percentage yield and atom economy.
Key idea: Mole calculations depend on the balanced equation, relative formula mass, amount in moles and the relationship between theoretical and practical quantities.
Masses
Comparing Masses of Substances
Revise relative atomic mass, relative formula mass and how chemists compare the masses of particles and compounds.
Equation
Calculations involving Moles
Practise using amount of substance, mass and relative formula mass in the core mole calculation relationship.
Masses
Calculations using Reacting Masses
Use balanced equations and mole ratios to calculate the mass of reactants needed or products formed.
Yield
The Yield of a Reaction
Understand theoretical yield, actual yield and why percentage yield is often less than 100% in practical chemistry.
Economy
Atom Economy
Revise how atom economy measures the proportion of reactant atoms converted into the desired product.
How These Pages Fit Together
Start with relative masses, then move to the mole equation. Once the amount in moles is secure, reacting mass calculations become a matter of using the balanced equation ratio correctly.
Percentage yield and atom economy then extend the same quantitative ideas into practical efficiency and green chemistry. These two ideas are especially useful for exam questions that ask students to interpret why a reaction may not produce the maximum possible useful product.
Exam focus: Always convert through moles when comparing different substances in a balanced chemical equation.
OLS Author Copyright Footprint: This OLS revision landing page was created for Online Learning System by Dr. Mohammed Al-Fatah. All content, layout and educational sequencing are part of the OLS Revision Notes project.