At a glance
Individual · three hours, in the examination period · written, with a data booklet and a calculator · the whole course, weighted toward the calculations you have done most
What it is for
Everything else this semester was done with a partner, a bench, and time to check. This is the one piece of evidence that is unambiguously yours, produced under the same conditions as everybody else’s. It is not there to catch anyone out — it is there so that what you personally understand is on the record.
What is on it
| Part | Roughly | What it asks you to do |
|---|---|---|
| A. Naming, formulas, and equations | 20% | Name compounds, write formulas, balance and classify reactions |
| B. Calculations | 40% | Moles, molar mass, empirical formulas, stoichiometry, limiting reagent and yield, concentration, gas laws |
| C. Reading an investigation | 25% | Given data from an experiment you have not seen: process it, state what it shows, and say what its uncertainty allows you to claim |
| D. Chemistry and the world | 15% | Short answers on solutions, the atmosphere, industrial processes, and safe practice |
Part B is the largest because it is what the course spends its time on. Part C is the part students underestimate: it is not a memory question, and the marks are in the reasoning.
What to expect, precisely
- Every calculation shows its route. A bare answer earns almost nothing; a clearly wrong number reached by a correct method earns most of the marks. Units at every step, and a final answer with the right significant figures — Significant Figures and Units is the rule you will be held to.
- A data booklet is provided: periodic table, Polyatomic Ions, Solubility Rules, The Activity Series, and the gas constants. You do not memorise those. You memorise how to use them.
- The investigation question gives you a table of measurements. You will process it, plot or describe the relationship, and state a conclusion with its uncertainty, exactly as in Writing a Lab Report.
- Balanced equations are expected to be balanced. It is the cheapest mark in the paper and the most commonly dropped.
How to prepare
- Redo calculations, do not reread them. Take five problems from each unit’s practice set and work them cold, on paper, with the data booklet only.
- Rebuild the connections. Mole → mass → particles → volume → concentration is one map, not five topics. Draw it from memory; the gaps you find are your study list.
- Re-read your own lab reports. Your Chemistry Journal entries about what went wrong at the bench are the most efficient revision there is, because you wrote them at the moment of understanding.
- Practise the naming until it is boring. Naming Practice and Naming Rules at a Glance; twenty minutes a night beats three hours the day before.
- Bring questions to the review classes. This page is what is on the examination — the review classes are for the parts of it you cannot yet do.
In the three hours
Do Part B second, not first: warm up on the naming, then spend your freshest hour on the calculations. If a calculation stalls, write the route you intended in words and move on — a described method earns marks, and a blank space earns none.
How this is assessed
Against the same expectations as everything else. Per How Marks Work, this examination is part of the final 30% of the course mark alongside The Chemistry Showcase — deliberately, so that neither one afternoon nor one investigation decides your grade alone.
Curriculum connection
A1.8
synthesize, analyse, interpret, and evaluate qualitative and quantitative data; solve problems involving quantitative data; determine whether the evidence supports or refutes the initial prediction or hypothesis and whether it is consistent with scientific theory; identify sources of bias and error; and suggest improvements to the inquiry to reduce the likelihood of error
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B3.2
explain the relationship between isotopic abundance of an element’s isotopes and the relative atomic mass of the element
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C3.3
explain the chemical reactions that result in the formation of acids and bases from metal oxides and non-metal oxides (e.g., calcium oxide reacts with water to produce a basic solution; carbon dioxide reacts with water to produce an acidic solution)
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D3.2
describe the relationships between Avogadro’s number, the mole concept, and the molar mass of any given substance
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E3.3
explain the effects of changes in temperature and pressure on the solubility of solids, liquids, and gases (e.g., explain how a change in temperature or atmospheric pressure affects the solubility of oxygen in lake water)
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F2.3
solve quantitative problems by performing calculations based on Boyle’s law, Charles’s law, Gay-Lussac’s law, the combined gas law, Dalton’s law of partial pressures, and the ideal gas law [AI]
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F3.4
describe, for an ideal gas, the quantitative relationships that exist between the variables of pressure, volume, temperature, and amount of substance
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F3.5
explain Dalton’s law of partial pressures, Boyle’s law, Charles’s law, Gay-Lussac’s law, the combined gas law, and the ideal gas law
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