# 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
* •    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 M$_r$
* •    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 (dm$^3$) 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

#### 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

Example:
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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### Links

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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