Revision Notes MCQ Bank SAQ Bank Study Cards Courses Teachers Blog
Edexcel A Level Chemistry

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.

Exam Paper
Paper 1
9CH0/01
Specification Points
5.3 – 5.14
7 points covered
Sub-topics
5 lessons
Revision notes available
Exam Board
Edexcel
Pearson 9CH0

Revision Notes

5 revision notes, in the order the specification teaches them.

A balance comparing one heavy atom with twelve light ones
1

Comparing Masses of Substances

Revise relative atomic mass, relative formula mass and how chemists compare the masses of particles and compounds.

Start revising
A heap of powder opening out into countless particles
2

Calculations involving Moles

Practise using amount of substance, mass and relative formula mass in the core mole calculation relationship.

Start revising
Two piles of reactant in a fixed ratio
3

Calculations using Reacting Masses

Use balanced equations and mole ratios to calculate the mass of reactants needed or products formed.

Start revising
A flask holding less product than the full amount
4

The Yield of a Reaction

Understand theoretical yield, actual yield and why percentage yield is often less than 100% in practical chemistry.

Start revising
A wanted molecule with a small waste fragment breaking away
5

Atom Economy

Revise how atom economy measures the proportion of reactant atoms converted into the desired product.

Start revising

Summary Map

Download, print and revise the key facts of this topic at a glance.

Summary map

Download, print and revise the key facts of this topic at a glance.

Illustration of a summary map: compounds joined by reaction arrows
Summary map · PDF

Mole Calculations Map

Edexcel A Level Chemistry · Topic 5 Formulae, Equations and Amounts of Substance · Mole Calculations

The whole section on one A4 page: relative and molar masses, the mole and the Avogadro constant, reacting masses, yield, atom economy and formulae by experiment.

Download the map6 key ideas + an equations table · A4 portrait · print ready

© 2026 Online Learning System. For personal study: printing is allowed; editing, copying and redistribution are not.

Virtual Lessons

Recorded video lessons that teach the topic step by step.

Coming soon

The Virtual Lessons for Topic 5 - Formulae, Equations and Amounts of Substance are being recorded.

MCQ Bank

Multiple-choice papers on this topic, marked the moment you submit. MCQ (A) is free.

Illustration of a multiple-choice paper with one answer tickedMCQ (A) free

Test yourself: 8 MCQ papers

Exam-style multiple-choice papers, marked the moment you submit with every answer explained. MCQ (A) is free.

8 exam-style multiple-choice papers, MCQ (A) to (H): 170 questions on Topic 5 Formulae, Equations and Amounts of Substance, written the way the exam asks them.

  • Marked the moment you submitYour score straight away, with every answer explained, right or wrong.
  • Revise what you missedEach explanation links to the revision notes for that point.
  • MCQ (A) is freeTry the first paper now. MCQ (B) to (H) come with the course.
Open this topic in the MCQ Bank

SAQ Bank

Written, drawn and worked exam practice on this topic.

Coming soon

The exam practice papers for Topic 5 - Formulae, Equations and Amounts of Substance are being written.

Open the SAQ Bank

Revision Game

Match reagents to products, with your board's reagents and conditions.

Coming soon

The revision game for Topic 5 - Formulae, Equations and Amounts of Substance is being built.

Study Cards

Pick a deck, then turn each card to check what you remember.

Specification

Every specification point in this topic, in the exam board's own words. Rate how confident you are with each one.

Official Pearson Edexcel documentsSpecification (opens the Pearson Edexcel website in a new tab)Data booklet (opens the Pearson Edexcel website in a new tab)

Self-assessment · 38 points

Sign in to rate how confident you feel about each point. Your ratings are saved to your account, follow you to any device, and appear beside your KASP analytics, kept apart from your marks.

Sign in to rate yourself
0 Confident0 Getting there0 Not yet38 Not rated

5.1

  1. 5.1

    know that the mole (mol) is the unit for amount of a substance

    Revise

5.2

  1. 5.2

    be able to use the Avogadro constant, L, (6.02 × 1023 mol-1) in calculations

    Revise

5.3

  1. 5.3

    know that the molar mass of a substance is the mass per mole of the substance in g mol-1

    Revise

5.4

  1. a

    know what is meant by empirical formula

    Revise
  2. b

    know what is meant by molecular formula

    Revise

5.5

  1. a

    be able to use experimental data to calculate empirical formulae

    Revise
  2. b

    be able to use experimental data to calculate molecular formulae

    Revise
  3. c

    be able to use pV = nRT for gases and volatile liquids in empirical/molecular formula calculations

    Revise
  4. d

    know that empirical formula calculations may involve composition by mass data

    Revise
  5. e

    know that empirical formula calculations may involve percentage composition by mass data

    Revise

5.6

  1. a

    be able to write balanced full equations, including state symbols, for chemical reactions

    Revise
  2. b

    be able to write balanced ionic equations, including state symbols, for chemical reactions

    Revise

5.7

  1. a

    be able to calculate amounts of substance in reactions involving mass

    Revise
  2. b

    be able to calculate amounts of substance in reactions involving volume of gas

    Revise
  3. c

    be able to calculate amounts of substance in reactions involving volume of solution

    Revise
  4. d

    be able to calculate amounts of substance in reactions involving concentration

    Revise
  5. e

    know these calculations may involve reactants

    Revise
  6. f

    know these calculations may involve products

    Revise

5.8

  1. 5.8

    be able to calculate reacting masses from chemical equations, and vice versa, using the concepts of amount of substance and molar mass

    Revise

5.9

  1. 5.9

    be able to calculate reacting volumes of gases from chemical equations, and vice versa, using the concepts of amount of substance

    Revise

5.10

  1. 5.10

    be able to calculate reacting volumes of gases from chemical equations, and vice versa, using the concepts of molar volume of gases

    Revise

5.11

  1. a

    be able to calculate solution concentrations in mol dm-3

    Revise
  2. b

    be able to calculate solution concentrations in g dm-3

    Revise
  3. c

    be able to carry out simple acid-base titration calculations using a range of acids, alkalis and indicators

    Revise
  4. d

    know the use of phenolphthalein as an indicator

    Revise
  5. e

    know the use of methyl orange as an indicator

    Revise

5.12

  1. i

    be able to: calculate measurement uncertainties and measurement errors in experimental results

    Revise
  2. ii

    be able to: comment on sources of error in experimental procedures

    Revise

5.13

  1. 5.13

    understand how to minimise the percentage error and percentage uncertainty in experiments involving measurements

    Revise

5.14

  1. a

    be able to calculate percentage yields using chemical equations and experimental results

    Revise
  2. b

    be able to calculate percentage atom economies using chemical equations and experimental results

    Revise
  3. c

    know that atom economy = molar mass of desired product × 100% / sum of molar masses of all products

    Revise

5.15

  1. i

    be able to relate ionic and full equations, with state symbols, to observations from simple test tube reactions, to include: displacement reactions

    Revise
  2. ii

    be able to relate ionic and full equations, with state symbols, to observations from simple test tube reactions, to include: reactions of acids

    Revise
  3. iii

    be able to relate ionic and full equations, with state symbols, to observations from simple test tube reactions, to include: precipitation reactions

    Revise

5.16

  1. a

    understand risks in practical procedures

    Revise
  2. b

    understand hazards in practical procedures

    Revise
  3. c

    suggest appropriate precautions where necessary

    Revise