Applied Science AQA/Amount of Substance

Topic Title


Setting Applied context


Chemical engineers and synthetic chemists rely on their knowledge of mole and reaction stoichiometries to determine reacting masses and yields for large-scale industrial production of chemicals. Analytical chemists also apply similar concepts in quantitative analysis, together with the selection of correct reagents to ensure accuracy of outcomes. 

Syllabus Content What you need to do
•    the mole as the amount of a substance that always contains the same number of entities (eg atoms, molecules, ions, electrons)

•    the relationship between mass of substance and amount in moles, moles = mass Mr

•    the relationship between volume of gas at RTP and STP and amount in moles, PV = nRT

•    concentrations of solutions in terms of mol dm–3 and g dm–3

•    molecular formulas

•    empirical formulas

•    calculating empirical formulas

•    writing balanced equations for typical reactions including:

•    acid–base neutralisation

•    thermal decomposition

•    acid/metal

•    acid/carbonate

•    precipitation

•    combustion reactions

•    calculating reacting masses based on correct stoichiometries

•    equivalence point of an acid–base titration

•    how the choice of indicator for an acid–base titration depends on the types (strengths) of acid and base used and the resulting pH titration curve

•    calculating unknown concentrations and volumes from results involving volumetric analysis (limited to acid–base titrations); moles = vol (dm3) x concentration (mol dm–3)

•    plotting and interpreting pH curves.

Exploration of key ideas (must be original text, not C&P) – level checked by AQA


In general, point students towards the approach to take, as opposed to just giving them information.

Concept 1


explanation 1

mad scientist

Concept 2


explanation 2

Concept 3


explanation 3

Concept 4


explanation 4

Study Task


Work to do to understand this topic e.g. research, analysis

Careers and Organisations


Carry out some research into these jobs in this area. (Feel free to add other jobs you find.)

Research these roles: What are the benefits of this role to society? What organisations would employ someone in this role? 

(Where would they work?)

What would someone in this role have to do within the organisation? What scientifically-related skills do they need to have? 

What techniques do they need to have mastered?

What experience is needed to undertake this role and its responsibilities within an organisation? What other science personnel will they work with in their organisation.
Job 1
Job 2

Relevant practical/s


– relating to criteria skills

Quick questions



quick questions


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Exam-style questions


– can we use old AQA qs… e.g. from more than 5 years ago? With Examiner comments


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to other sections within this book

to good external websites (including AQA website, wikipedia, relevant applications / companies) - also considering links in spec

References / Bibliography


of recommended text books

including mapped refs to existing books

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