Master the AQA AS Level Chemistry (7404) exams with this expert, evidence-based guide. Explore proven examiner strategies, precise mathematical conversion pathways, mechanism curly-arrow rules, and critical adjustments to secure top marks in physical, inorganic, and organic chemistry.
阅读时间 4 分钟更新于: 2026年6月21日
试卷概览
卷数
2
总分
160
考试时间
3小时
题型
2
试卷
时间
分数
题数
比重
题型
Paper 1: Inorganic and Physical Chemistry
1小时 30分钟
80
24
50%
Structured Written Questions, 選擇題
Paper 2: Organic and Physical Chemistry
1小时 30分钟
80
22
50%
Structured Written Questions, 選擇題
评级
ABCDEU
计算器规定
A scientific or graphical calculator that meets JCQ regulations may be used (some GCSE Mathematics and Science papers are non-calculator). Graphical calculators must be set to exam mode; you must clear any stored programs, notes or data before the exam, and the calculator must not be able to retrieve stored text or formulae.
AO1: AO1: Demonstrate knowledge and understanding of scientific ideas, processes, techniques and procedures (35%)
AO2: AO2: Apply knowledge and understanding of scientific ideas, processes, techniques and procedures (45%)
AO3: AO3: Analyse, interpret and evaluate scientific information, ideas and evidence (20%)
根据历届试题与评分标准整理（2022–2024）。
计算器程序
Graph: zeros, intersections & turning points
Graphical calculator / GDC (exam mode)
用途: Plot a function to read its roots (zeros), points of intersection, and maxima/minima.
使用时机: Checking solutions, sketching, or solving where an analytic method is hard.
步骤
Graph the function(s) and use the built-in zero, intersect and maximum/minimum tools.
考试提示: Allowed under JCQ rules, but you must still show your method — an unsupported calculator answer earns no method marks. Clear all stored programs, notes and data (graphical calculators in exam mode) before the exam.
Numerical equation solver
Graphical calculator / GDC (exam mode)
用途: Solve an equation or find a variable numerically when an algebraic route is long or implicit.
使用时机: Iterative or implicit equations, or to confirm an algebraic solution.
步骤
Use the equation/zero solver, entering the equation and a sensible starting estimate.
考试提示: Allowed under JCQ rules, but you must still show your method — an unsupported calculator answer earns no method marks. Clear all stored programs, notes and data (graphical calculators in exam mode) before the exam.
Numerical integration & differentiation
Graphical calculator / GDC (exam mode)
用途: Evaluate a definite integral \(\int_a^b f(x)\,dx\) or a gradient \(f'(x)\) at a point.
使用时机: Checking calculus answers, or where only a numerical value is needed.
步骤
Use the GDC's numeric integral / derivative function with the limits or the point.
考试提示: Allowed under JCQ rules, but you must still show your method — an unsupported calculator answer earns no method marks. Clear all stored programs, notes and data (graphical calculators in exam mode) before the exam.
Statistics & probability distributions
Graphical calculator / GDC (exam mode)
用途: 1-var/2-var statistics, linear regression, and cumulative binomial / normal / Poisson probabilities without tables.
使用时机: Statistics questions and hypothesis tests.
步骤
Enter data in the statistics editor, or use the distribution menu (binomial cdf, normal cdf, …).
考试提示: Allowed under JCQ rules, but you must still show your method — an unsupported calculator answer earns no method marks. Clear all stored programs, notes and data (graphical calculators in exam mode) before the exam.
常见错误
1high涉及分数: 2Amount of substance
Failing to convert volume from cm3 to m3 in the ideal gas equation (PV=nRT).
如何避免: Always multiply the volume in cm3 by 10^-6 to convert it to m3 before using it in the equation.
2high涉及分数: 1Introduction to organic chemistry
Drawing curly arrows in organic mechanisms originating from atoms or signs instead of lone pairs or covalent bonds.
如何避免: Ensure every curly arrow starts precisely from a lone pair of electrons or from the center of a covalent/double bond.
3medium涉及分数: 1Amount of substance
Forgetting that a balance involves a 'before' and 'after' reading (two measurements), leading to incorrect percentage uncertainty calculations.
如何避免: Always double the absolute uncertainty of a balance reading (e.g., 2 x +/- 0.005g = 0.010g absolute uncertainty) before dividing by the mass recorded.
4medium涉及分数: 1Amount of substance
Rinsing a titration burette with distilled water without subsequently rinsing it with the titrant solution.
如何避免: Rinse the burette with distilled water to clean it, but always perform a final rinse with the exact titrant solution to prevent dilution of the standard solution.
5high涉及分数: 2Alkenes
Stating that the major product of an alkene addition is formed because the product itself is more stable, rather than explaining the stability of the intermediate carbocation.
如何避免: Always refer to the intermediate: state that the reaction proceeds via a more stable tertiary (or secondary) carbocation intermediate due to the greater positive inductive effect of alkyl groups.
6high涉及分数: 1Atomic structure
Omission of state symbols in gaseous ionization equations, such as those required for mass spectrometry or ionisation energies.
如何避免: Double-check that every species in an ionisation energy equation has the (g) state symbol, e.g., Na+(g) -> Na2+(g) + e-.
7medium涉及分数: 2Group 7(17), the halogens
Confusing standard halide tests, specifically omitting the 'dilute' vs 'concentrated' ammonia step when distinguishing silver chloride from silver bromide precipitates.
如何避免: Specify that silver chloride dissolves in DILUTE ammonia, whereas silver bromide only dissolves in CONCENTRATED ammonia.