6/27/25, 12:32 PM AQA A-Level Chemistry Paper 3 EXAM | ALL QUESTIONS AND CORRECT ANSWERS | GRADED A+ | VERIFIED ANSWERS | …
AQA A-Level Chemistry Paper 3 EXAM | ALL QUESTIONS AND
CORRECT ANSWERS | GRADED A+ | VERIFIED ANSWERS |
NEWEST VERSION 2025-2026
Key apparatus for Volumetric flask, pipette and filler, burette, conical flask, white
preparation of a standard tile.
solution?
How do you ensure an Use a mass balance to weigh solute accurately, dissolve
accurate standard fully in deionised water, and rinse all equipment into
solution? the volumetric flask before making up to the line.
Why is a white tile used in To help detect the colour change more clearly at the end point.
titrations?
What indicators are used in Phenolphthalein (pink in alkali, colourless in acid) or
acid-base titrations and methyl orange (yellow in alkali, red in acid) -
why? depending on strong/weak acid or base used.
How do you ensure Repeat until concordant titres (within 0.1 cmr), swirl the
accurate titration results? flask, add dropwise near end point, rinse burette tip.
How is heat energy calculated? ∆Q = mc∆T
Why might your result be Heat loss to surroundings, incomplete combustion, evaporation
less exothermic than of fuel or solution.
expected when measuring
enthalpy change?
How can calorimetry be Use a lid, insulate the container, use a bomb calorimeter for
improved? combustion reactions.
What are the main sources Heat loss, inaccurate temperature readings, assuming
of error in calorimetry? solution has same heat capacity as water.
What visual method is used Time how long it takes for a cross to disappear under the flask as
in the thiosulfate reaction? sulfur precipitates.
How does increasing Increases frequency of collisions, leading to a faster rate.
concentration affect rate?
What is a control variable in Temperature, volume of solutions, same person judging
… 1/4
AQA A-Level Chemistry Paper 3 EXAM | ALL QUESTIONS AND
CORRECT ANSWERS | GRADED A+ | VERIFIED ANSWERS |
NEWEST VERSION 2025-2026
Key apparatus for Volumetric flask, pipette and filler, burette, conical flask, white
preparation of a standard tile.
solution?
How do you ensure an Use a mass balance to weigh solute accurately, dissolve
accurate standard fully in deionised water, and rinse all equipment into
solution? the volumetric flask before making up to the line.
Why is a white tile used in To help detect the colour change more clearly at the end point.
titrations?
What indicators are used in Phenolphthalein (pink in alkali, colourless in acid) or
acid-base titrations and methyl orange (yellow in alkali, red in acid) -
why? depending on strong/weak acid or base used.
How do you ensure Repeat until concordant titres (within 0.1 cmr), swirl the
accurate titration results? flask, add dropwise near end point, rinse burette tip.
How is heat energy calculated? ∆Q = mc∆T
Why might your result be Heat loss to surroundings, incomplete combustion, evaporation
less exothermic than of fuel or solution.
expected when measuring
enthalpy change?
How can calorimetry be Use a lid, insulate the container, use a bomb calorimeter for
improved? combustion reactions.
What are the main sources Heat loss, inaccurate temperature readings, assuming
of error in calorimetry? solution has same heat capacity as water.
What visual method is used Time how long it takes for a cross to disappear under the flask as
in the thiosulfate reaction? sulfur precipitates.
How does increasing Increases frequency of collisions, leading to a faster rate.
concentration affect rate?
What is a control variable in Temperature, volume of solutions, same person judging
… 1/4
