1
AQA A-LEVEL CHEMISTRY PAPER 3 2026/2027 |
CHEMISTRY | 100 VERIFIED Q&A | DETAILED
RATIONALES | PASS GUARANTEED – A+ GRADED
SECTION 1: PRACTICAL SKILLS & TECHNIQUES - Questions 1-20
Q1: Titration – Rinsing the Burette
The student is reviewing titration technique. Before filling a burette with the solution it will deliver,
the burette should be rinsed with:
A. Deionised water only
B. The solution it will contain
C. The solution in the conical flask
D. Acid
Correct Answer: B
Rationale: Rinsing with the solution to be used ensures no dilution of the solution by residual water,
which would affect the concentration. Rinsing with deionised water would leave water droplets that
dilute the titrant. [100% CORRECT]
Q2: Titration – Rinsing the Pipette
The student is reviewing titration. A pipette used to measure 25.0 cm³ of solution should be rinsed
with:
A. Deionised water
B. The solution it will contain
C. The titrant
D. Acid
Correct Answer: B
Rationale: Rinsing the pipette with the solution it will contain prevents dilution of the measured
aliquot. Rinsing with water would leave water droplets. [100% CORRECT]
Q3: Titration – Conical Flask
The student is reviewing titration. The conical flask should be rinsed with:
A. Deionised water
B. The solution it will contain
C. The titrant
D. Acid
,2
Correct Answer: A
Rationale: The conical flask is rinsed with deionised water only. Any water remaining does not affect
the number of moles of the measured aliquot, so it does not affect the titre. [100% CORRECT]
Q4: Titration – Concordant Results
The student is reviewing titration. Concordant titres are within:
A. 0.10 cm³
B. 0.50 cm³
C. 1.00 cm³
D. 0.01 cm³
Correct Answer: A
Rationale: Concordant titres are within 0.10 cm³ of each other. They are used to calculate a mean
titre. [100% CORRECT]
Q5: Titration – Indicator Choice
The student is reviewing titration. For a strong acid–weak base titration, a suitable indicator is:
A. Phenolphthalein
B. Methyl orange
C. Universal indicator
D. Litmus
Correct Answer: B
Rationale: Strong acid–weak base titration has an acidic equivalence point (pH < 7). Methyl orange
(pH range 3.1–4.4) is suitable. Phenolphthalein (pH 8.3–10.0) is suitable for weak acid–strong base.
[100% CORRECT]
Q6: Measuring Mass
The student is reviewing practical skills. When weighing a solid, the correct method is:
A. Weigh the empty container, add solid, reweigh, and subtract
B. Weigh the solid directly on the balance pan
C. Weigh the container after adding solid only
D. Estimate the mass
Correct Answer: A
Rationale: Weighing by difference: mass of container + solid minus mass of empty container gives
mass of solid. This avoids transferring errors. [100% CORRECT]
Q7: Heating to Constant Mass
, 3
The student is reviewing practical skills. Heating to constant mass means:
A. Heating, cooling, weighing, and repeating until mass is constant
B. Heating once
C. Heating for a fixed time
D. Heating until no more gas evolves
Correct Answer: A
Rationale: Heating to constant mass ensures all volatile products have been removed. The process is
repeated until consecutive weighings agree. [100% CORRECT]
Q8: Recrystallisation – Hot Solvent
The student is reviewing purification. In recrystallisation, the impure solid is dissolved in:
A. Cold solvent
B. Hot solvent
C. Water only
D. Acid
Correct Answer: B
Rationale: The solid is dissolved in the minimum volume of hot solvent. On cooling, pure crystals
form, leaving impurities in solution. [100% CORRECT]
Q9: Recrystallisation – Filtration
The student is reviewing purification. Hot filtration is used to:
A. Remove insoluble impurities
B. Remove soluble impurities
C. Dry the crystals
D. Melt the crystals
Correct Answer: A
Rationale: Hot filtration removes insoluble impurities before crystallisation. Soluble impurities
remain in the filtrate. [100% CORRECT]
Q10: Drying Crystals
The student is reviewing purification. Crystals are dried in a desiccator to:
A. Remove water without heating
B. Melt them
C. Dissolve them
D. React them
Correct Answer: A
AQA A-LEVEL CHEMISTRY PAPER 3 2026/2027 |
CHEMISTRY | 100 VERIFIED Q&A | DETAILED
RATIONALES | PASS GUARANTEED – A+ GRADED
SECTION 1: PRACTICAL SKILLS & TECHNIQUES - Questions 1-20
Q1: Titration – Rinsing the Burette
The student is reviewing titration technique. Before filling a burette with the solution it will deliver,
the burette should be rinsed with:
A. Deionised water only
B. The solution it will contain
C. The solution in the conical flask
D. Acid
Correct Answer: B
Rationale: Rinsing with the solution to be used ensures no dilution of the solution by residual water,
which would affect the concentration. Rinsing with deionised water would leave water droplets that
dilute the titrant. [100% CORRECT]
Q2: Titration – Rinsing the Pipette
The student is reviewing titration. A pipette used to measure 25.0 cm³ of solution should be rinsed
with:
A. Deionised water
B. The solution it will contain
C. The titrant
D. Acid
Correct Answer: B
Rationale: Rinsing the pipette with the solution it will contain prevents dilution of the measured
aliquot. Rinsing with water would leave water droplets. [100% CORRECT]
Q3: Titration – Conical Flask
The student is reviewing titration. The conical flask should be rinsed with:
A. Deionised water
B. The solution it will contain
C. The titrant
D. Acid
,2
Correct Answer: A
Rationale: The conical flask is rinsed with deionised water only. Any water remaining does not affect
the number of moles of the measured aliquot, so it does not affect the titre. [100% CORRECT]
Q4: Titration – Concordant Results
The student is reviewing titration. Concordant titres are within:
A. 0.10 cm³
B. 0.50 cm³
C. 1.00 cm³
D. 0.01 cm³
Correct Answer: A
Rationale: Concordant titres are within 0.10 cm³ of each other. They are used to calculate a mean
titre. [100% CORRECT]
Q5: Titration – Indicator Choice
The student is reviewing titration. For a strong acid–weak base titration, a suitable indicator is:
A. Phenolphthalein
B. Methyl orange
C. Universal indicator
D. Litmus
Correct Answer: B
Rationale: Strong acid–weak base titration has an acidic equivalence point (pH < 7). Methyl orange
(pH range 3.1–4.4) is suitable. Phenolphthalein (pH 8.3–10.0) is suitable for weak acid–strong base.
[100% CORRECT]
Q6: Measuring Mass
The student is reviewing practical skills. When weighing a solid, the correct method is:
A. Weigh the empty container, add solid, reweigh, and subtract
B. Weigh the solid directly on the balance pan
C. Weigh the container after adding solid only
D. Estimate the mass
Correct Answer: A
Rationale: Weighing by difference: mass of container + solid minus mass of empty container gives
mass of solid. This avoids transferring errors. [100% CORRECT]
Q7: Heating to Constant Mass
, 3
The student is reviewing practical skills. Heating to constant mass means:
A. Heating, cooling, weighing, and repeating until mass is constant
B. Heating once
C. Heating for a fixed time
D. Heating until no more gas evolves
Correct Answer: A
Rationale: Heating to constant mass ensures all volatile products have been removed. The process is
repeated until consecutive weighings agree. [100% CORRECT]
Q8: Recrystallisation – Hot Solvent
The student is reviewing purification. In recrystallisation, the impure solid is dissolved in:
A. Cold solvent
B. Hot solvent
C. Water only
D. Acid
Correct Answer: B
Rationale: The solid is dissolved in the minimum volume of hot solvent. On cooling, pure crystals
form, leaving impurities in solution. [100% CORRECT]
Q9: Recrystallisation – Filtration
The student is reviewing purification. Hot filtration is used to:
A. Remove insoluble impurities
B. Remove soluble impurities
C. Dry the crystals
D. Melt the crystals
Correct Answer: A
Rationale: Hot filtration removes insoluble impurities before crystallisation. Soluble impurities
remain in the filtrate. [100% CORRECT]
Q10: Drying Crystals
The student is reviewing purification. Crystals are dried in a desiccator to:
A. Remove water without heating
B. Melt them
C. Dissolve them
D. React them
Correct Answer: A
