This expert guide offers evidence-based strategies, precise calculator techniques, and vital mark-scheme rules to excel in Oxford AQA International AS Level Chemistry (9620).
อ่าน 4 นาทีอัปเดตเมื่อ: 21 มิ.ย. 2569
ภาพรวมข้อสอบ
จำนวนฉบับ
3
คะแนนเต็ม
220
เวลาสอบ
4ชม. 30นาที
ประเภทคำถาม
3
ฉบับ
เวลา
คะแนน
จำนวนข้อ
น้ำหนักคะแนน
ประเภทคำถาม
Unit 1: Inorganic 1 and Physical 1
1ชม. 30นาที
70
24
35%
Structured Short Answer, Mathematical Calculations, Tick-the-Box Multiple Choice
Unit 2: Organic 1 and Physical 1
1ชม. 30นาที
70
23
35%
Structured Short Answer & Drawing, Mathematical Calculations, Tick-the-Box Multiple Choice
Unit 3: Inorganic 2 and Physical 2
1ชม. 30นาที
80
26
30%
Structured Short Answer & Complexes, Mathematical Calculations, Tick-the-Box Multiple Choice
เกณฑ์เกรด
A*ABCDEU
ข้อกำหนดเครื่องคิดเลข
A scientific or graphical calculator is permitted. Graphical calculators must be in exam mode with all stored programs and data cleared before the exam; the calculator must not be able to retrieve stored text or formulae.
วัตถุประสงค์: Plot a function to read its roots (zeros), points of intersection, and maxima/minima.
ใช้เมื่อใด: Checking solutions, sketching, or solving where an analytic method is hard.
ขั้นตอน
Graph the function(s) and use the built-in zero, intersect and maximum/minimum tools.
ข้อควรระวังในการสอบ: Allowed, but clear stored programs/data (graphical calculators in exam mode) and show the required working — unsupported calculator answers score no method marks.
Numerical equation solver
Graphical calculator / GDC (exam mode)
วัตถุประสงค์: Solve an equation or find a variable numerically when an algebraic route is long or implicit.
ใช้เมื่อใด: Iterative or implicit equations, or to confirm an algebraic solution.
ขั้นตอน
Use the equation/zero solver, entering the equation and a sensible starting estimate.
ข้อควรระวังในการสอบ: Allowed, but clear stored programs/data (graphical calculators in exam mode) and show the required working — unsupported calculator answers score no method marks.
Numerical integration & differentiation
Graphical calculator / GDC (exam mode)
วัตถุประสงค์: Evaluate a definite integral \(\int_a^b f(x)\,dx\) or a gradient \(f'(x)\) at a point.
ใช้เมื่อใด: Checking calculus answers, or where only a numerical value is needed.
ขั้นตอน
Use the GDC's numeric integral / derivative function with the limits or the point.
ข้อควรระวังในการสอบ: Allowed, but clear stored programs/data (graphical calculators in exam mode) and show the required working — unsupported calculator answers score no method marks.
Statistics & probability distributions
Graphical calculator / GDC (exam mode)
วัตถุประสงค์: 1-var/2-var statistics, linear regression, and cumulative binomial / normal / Poisson probabilities without tables.
ใช้เมื่อใด: Statistics questions and hypothesis tests.
ขั้นตอน
Enter data in the statistics editor, or use the distribution menu (binomial cdf, normal cdf, …).
ข้อควรระวังในการสอบ: Allowed, but clear stored programs/data (graphical calculators in exam mode) and show the required working — unsupported calculator answers score no method marks.
ข้อผิดพลาดที่พบบ่อย
1highคะแนนที่เกี่ยวข้อง: 2Atomic structure
Failing to convert molar mass from g/mol to kg/ion in TOF mass spectrometry calculations.
วิธีหลีกเลี่ยง: Always divide the mass of a mole (g) by Avogadro's constant to find the mass of a single atom/ion, and then divide by 1000 to convert grams to kilograms (kg).
2highคะแนนที่เกี่ยวข้อง: 1Introduction to organic chemistry
Drawing curly arrows that originate from the wrong focus point (such as a hydrogen atom or empty space).
วิธีหลีกเลี่ยง: Ensure all curly arrows originate strictly from a lone pair of electrons or from the center of a covalent/double bond, pointing precisely to the atom forming the new bond.
3mediumคะแนนที่เกี่ยวข้อง: 1Chemical equilibria, Le Chatelier’s principle and Kc
Using round brackets instead of square brackets in equilibrium constant (Kc) expressions.
วิธีหลีกเลี่ยง: Always use square brackets [ ] for Kc expressions. Round brackets represent mathematical grouping and will be completely penalized.
4highคะแนนที่เกี่ยวข้อง: 1Energetics
Omitting state symbols in Born-Haber cycle diagrams or ionization energy equations.
วิธีหลีกเลี่ยง: Double-check that all gaseous ions (e.g., Ba2+(g) or O2-(g)) have their state symbols explicitly written down, as examiners treat state symbols as essential.
5mediumคะแนนที่เกี่ยวข้อง: 2Amount of substance
Calculating the pH of a diprotic base (like barium hydroxide) without doubling the hydroxide ion concentration.
วิธีหลีกเลี่ยง: Remember that Ba(OH)2 dissociates to release 2 moles of OH- ions per mole of base. Multiply the base concentration by 2 before calculating pOH or using Kw.