Mole Calculations
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.
These pages cover the mole, formulae and every calculation type; hydrated salts and measuring techniques follow with the supplementary set.
Revision Notes
5 revision notes, in the order the specification teaches them.
Comparing Masses of Substances
Revise relative atomic mass, relative formula mass and how chemists compare the masses of particles and compounds.
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Calculations involving Moles
Practise using amount of substance, mass and relative formula mass in the core mole calculation relationship.
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Calculations using Reacting Masses
Use balanced equations and mole ratios to calculate the mass of reactants needed or products formed.
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The Yield of a Reaction
Understand theoretical yield, actual yield and why percentage yield is often less than 100% in practical chemistry.
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Atom Economy
Revise how atom economy measures the proportion of reactant atoms converted into the desired product.
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Summary map
Download, print and revise the key facts of this topic at a glance.
Moles and Masses Map
OCR A Level Chemistry A · 2.1.3 Amount of substance · Moles and masses
Moles and masses on one A4 page: amount of substance, the Avogadro constant, molar mass, reacting masses, yield, atom economy and sustainability.
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Revision Game
Match reagents to products, with your board's reagents and conditions.
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Specification
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2.1.3
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