OxfordAQA Paper 5 Framework

The 10 Required Practicals (RP1 to RP10)

The complete laboratory directory for OxfordAQA International AS & A-Level Chemistry (Specification 9620). Master apparatus setups, standard protocols, exact percentage uncertainty math, and high-yield Paper 5 exam differentiators across all 10 required practical activities.

Paper 5 Assessment Framework & Practical Competencies

OxfordAQA assesses experimental chemistry through written questions on Unit 5 (CH05) as well as throughout Units CH01 to CH04. Candidates are expected to demonstrate deep familiarity with the 10 core laboratory procedures specified in the 9620 Practical Handbook.

Core Laboratory Competencies Evaluated

  • Experimental Design: Selecting suitable glassware and apparatus with appropriate resolution and range.
  • Safety & Hazard Management: Identifying toxic, corrosive, and flammable hazards and detailing containment (fume cupboards, stop baths, PPE).
  • Uncertainty Mathematics: Calculating apparatus tolerances for pipettes, burettes (two readings), balances (mass by difference), and thermometers.
  • Graphical Analysis: Constructing tangents, calculating initial rates, evaluating Arrhenius plots, and reading half-neutralisation points.

Paper 5 Exam Strategy

Questions in Paper 5 often ask candidates to:

  • Critique a flawed student procedure and suggest specific corrections.
  • Sketch or identify errors in Quickfit ground-glass apparatus setups.
  • Account for differences between theoretical values and experimental outcomes.
  • Propose procedural changes that reduce the percentage uncertainty of a measurement.
OxfordAQA 10 Required Practicals Distribution Physical Practicals RP1: Volumetric Titration RP2: Enthalpy Calorimetry RP3: Rate with Temperature RP7: Continuous Monitoring RP8: Electrochemical EMF Inorganic & Analytical RP4: Qualitative Analysis Group 2, Halides, NH4+ RP9: pH Titration Curves Ka Determination Organic Practicals RP5: Distillation (Ethanal) RP6: Functional Group Tests RP10: Organic Solid Prep Reflux & Recrystallisation
Examiner Tip: Linking Practicals to Theory in Paper 5

Paper 5 questions never exist in a vacuum. Every practical procedure is intertwined with underlying quantitative theory: RP1 titration calculations feed back into mole ratios; RP2 calorimetry ties into Hess's law cycles; RP3 rate experiments lead to Arrhenius activation energy derivations; and RP9 pH titrations evaluate buffer equilibria and weak acid Ka.

All 10 Required Practical Walkthrough Guides

Click any guide below for full step-by-step procedures, apparatus diagrams, percentage uncertainty calculations, and exam-style worked examples:

RP1 CH01 / AS

Volumetric Solution & Acid-Base Titration

Prepare a standard volumetric solution using weighing by difference, and perform accurate titrations to determine an unknown concentration.

  • Weighing boat transfer with washings
  • Making up to 250 cm3 mark at eye level and inverting
  • Burette & pipette rinsing protocols
  • Concordant titres within 0.10 cm3
Open RP1 Guide →
RP2 CH02 / AS

Measurement of an Enthalpy Change

Measure temperature change in a solution reaction using an insulated polystyrene cup calorimeter, and calculate molar enthalpy change.

  • Minute-by-minute temperature logging
  • Cooling curve extrapolation back to mixing time
  • Heat calculation q = mc delta T
  • Molar enthalpy Delta H = -q / n
Open RP2 Guide →
RP3 CH02 / AS

Rate of Reaction with Temperature

Investigate the reaction rate between sodium thiosulfate and hydrochloric acid at varying temperatures using the disappearing cross technique.

  • Water bath temperature regulation
  • Timed precipitate obscuring black cross
  • Rate approximation: Rate = 1/t
  • Arrhenius plot for activation energy (Ea)
Open RP3 Guide →
RP4 CH01 / AS

Qualitative Inorganic Analysis

Systematic qualitative test-tube reactions to identify Group 2 cations (Mg2+, Ca2+, Sr2+, Ba2+), ammonium ions, halides, sulfates, and carbonates.

  • Group 2 solubility with NaOH and H2SO4
  • Ammonium test: warm NaOH + damp red litmus
  • Halide testing: acidified AgNO3 + dilute/conc NH3
  • Sulfate test with acidified BaCl2
Open RP4 Guide →
RP5 CH02 / AS

Distillation of an Organic Product

Synthesize and isolate a volatile organic liquid (e.g. oxidation of ethanol to ethanal) using Quickfit simple distillation glassware.

  • Quickfit assembly with water in at bottom/out at top
  • Thermometer bulb alignment with condenser side-arm
  • Anti-bumping granules to prevent surging
  • Open vent safety and ice bath collection
Open RP5 Guide →
RP6 CH02 / AS

Testing for Organic Functional Groups

Diagnostic chemical tests to identify alkenes, halogenoalkanes, alcohols, aldehydes, and carboxylic acids.

  • Alkenes: Bromine water decolourisation
  • Halogenoalkanes: Warm NaOH + HNO3 + AgNO3
  • Alcohols: Acidified K2Cr2O7 oxidation
  • Aldehydes: Tollens' silver mirror & Fehling's test
Open RP6 Guide →
RP7 CH03 / A2

Measuring Reaction Rates

Continuous monitoring of reaction progress (gas syringe volume vs time) and initial rate methods (iodine clock reaction).

  • Gas syringe setup for continuous collection
  • Drawing tangents at t = 0 for initial rates
  • Iodine clock reaction with variable concentration
  • Determining reaction orders and rate constants
Open RP7 Guide →
RP8 CH03 / A2

Measuring EMF of Electrochemical Cells

Construct electrochemical half-cells, measure cell potentials using a high-resistance voltmeter, and evaluate concentration effects.

  • Cleaning metal electrodes with emery paper
  • Salt bridge preparation (filter paper soaked in KNO3)
  • Measuring standard electrode potentials (E cell)
  • Le Chatelier shifts on half-cell voltages
Open RP8 Guide →
RP9 CH03 / A2

pH Titration Curves & Ka Determination

Calibrate a digital pH meter, record continuous titration curves, identify equivalence point vertical inflections, and deduce weak acid Ka.

  • pH meter calibration with buffer solutions (pH 4, 7, 10)
  • Fine volume increments near equivalence point
  • Half-neutralisation point: pH = pKa
  • Calculating Ka = 10^(-pH)
Open RP9 Guide →
RP10 CH04 / A2

Preparation & Purification of an Organic Solid

Synthesize an organic solid (e.g. aspirin) under reflux, filter using Buchner suction filtration, recrystallize with minimum hot solvent, and evaluate purity via melting point.

  • Synthesis under reflux with phosphoric acid catalyst
  • Buchner suction filtration and ice-cold washing
  • Recrystallisation from minimum hot solvent
  • Capillary melting point determination for purity
Open RP10 Guide →