CCEA GCSE Chemistry Higher Tier is dominated by organic chemistry, metals and quantitative work. This page maps the marks across all four units and fixes the recording and calculation habits that examiner reports flag every year.
阅读时间 3 分钟更新于: 2026年9月3日
试卷概览
卷数
4
总分
280
考试时间
5小时 45分钟
题型
12
试卷
时间
分数
题数
比重
题型
Unit 1: Structures, reactions & analysis
1小时 15分钟
80
5
35%
Symbol equations and dot-cross diagrams, Data tables and short recall, Quantitative stoichiometry, Extended response (QWC)
Unit 2: Rates, equilibrium & organic chemistry
1小时 30分钟
100
6
40%
Rates and energy calculations, Electrolysis and half-equations, Industrial metal extraction processes, Volumetric analysis stoichiometry, Extended response (QWC)
Unit 3: Practical (hands-on)
2小时
30
8
7.5%
Observation recording and pH testing, Enthalpy temperature and precipitate observations
Unit 3: Practical theory
1小时
70
5
17.5%
Halogen and halide identification, Gas law volume calculations, Experimental apparatus diagram and table design, Solubility graph interpretation and crystallisation, Extended response (QWC)
评级
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计算器规定
You may use a scientific calculator and the Data Leaflet on every paper in this subject. CCEA follows the JCQ rule that applies across all its exams: no calculator with a computer algebra system, no borrowing a calculator from another candidate, and nothing stored in memory that could be retrieved during the exam, including formulae, notes or text. If your calculator has an exam mode, switch it on. It clears stored data far more reliably than the reset button, which only resets display settings and leaves stored programs or text in memory.
AO1: AO1: demonstrate knowledge and understanding of scientific ideas, and scientific techniques and procedures (40%)
AO2: AO2: apply knowledge and understanding of and develop skills in scientific ideas, and scientific enquiry, techniques and procedures (40%)
AO3: AO3: analyse scientific information and ideas to interpret and evaluate, make judgements and draw conclusions, and develop and improve experimental procedures (20%)
Scale titration answers in one chained calculation
Casio fx-83/85 series (scientific)
用途: Stops the sample-to-flask scaling step, such as times 10 for a 25 cm3 sample from a 250 cm3 flask, from being forgotten or applied to a rounded figure.
使用时机: Any titration question where the sample analysed is a fraction of a larger volumetric flask.
步骤
After calculating moles or mass from the titration sample, multiply straight through by the scaling factor in the same calculator entry using the ANS key, rather than writing the unscaled figure down and retyping it.
考试提示: This is a live, in-exam technique. CCEA and JCQ ban anything stored in a calculator's memory before the exam, including formulae or previous working, so clear your calculator and switch on exam mode if it has one before you sit down.
Use memory recall for empirical formula ratios
Casio fx-83/85 series (scientific)
用途: Keeps mole ratios exact when dividing by the smallest value to find an empirical formula, instead of dividing by a rounded figure.
使用时机: Any empirical or molecular formula question comparing mole ratios of two or more elements.
步骤
Calculate the moles of each element, store the smallest value with the memory-store key (M+ or STO), then recall it (MR or RCL) to divide each of the other values by the exact figure rather than a rounded one.
考试提示: Use this only for values calculated during the exam itself. No programme or stored formula list is permitted, and a manual reset does not clear stored memory: use exam mode instead.
Calculate percentage yield and atom economy in one sequence
Casio fx-83/85 series (scientific)
用途: Stops the percentage sign being applied to the wrong part of the sum in a yield or atom economy calculation.
使用时机: Any percentage yield or atom economy question.
步骤
Enter actual divided by theoretical, or the atom economy equivalent, inside brackets, then multiply by 100 in the same calculation, so the order of operations is fixed by the brackets rather than by memory.
考试提示: This is a working method for the exam only. Clear your calculator's memory beforehand and do not rely on the reset button, which does not remove stored data.
常见错误
1medium涉及分数: 2Rates of reaction
Writing that a rate 'increases' or 'is faster' without saying why, omitting the collision frequency or particles-per-unit-time reasoning behind it.
如何避免: State the mechanism, not just the direction: increasing concentration or temperature increases the frequency of successful collisions per unit time.
2high涉及分数: 1Acids, bases and salts
Inverting the indicator colour change in titration descriptions, for example writing pink to colourless instead of colourless to pink when adding alkali to acid with phenolphthalein.
如何避免: Work out which reagent is in the flask and which is in the burette before describing the colour change, and write the starting colour first.
3medium涉及分数: 1Symbols, formulae and equations
Omitting state symbols when a question specifically asks for them in a balanced symbol or ionic equation.
如何避免: Once a question says 'include state symbols', treat every species as needing one, including (aq) for dissolved ions and (l) for water.
4high涉及分数: 3Quantitative chemistry
Forgetting the scaling multiplier when moving from a 25 cm3 titration sample back to a 250 cm3 volumetric flask, for example missing the times 10 step.
如何避免: Write the scaling factor as a separate labelled line in your working immediately after the titration calculation, before you move to the next step.
5high涉及分数: 2Electrochemistry
Placing electrons on the wrong side of electrolysis half-equations, or failing to balance charge, for example not writing 2Cl minus to Cl2 plus 2e minus correctly.
如何避免: Check the total charge on each side of a half-equation balances before moving on. Electrons go with the ions losing or gaining them, not on the product side by default.
6medium涉及分数: 2Acids, bases and salts
Believing a weak acid is the same as a dilute acid, rather than understanding that weak specifically means only partially ionised in water.
如何避免: Define weak and dilute separately every time: weak describes the degree of ionisation, dilute describes the concentration. A weak acid can be concentrated.
7medium涉及分数: 2Equilibrium
Believing an increase in pressure shifts an equilibrium toward the side with more moles of gas, the opposite of what actually happens.
如何避免: Learn the rule the right way round: increasing pressure shifts equilibrium toward the side with fewer gas moles, because that reduces the pressure again.