GCSE CHEMISTRY B (TWENTY FIRST CENTURY SCIENCE) — Actual June 2025 PAST
PAPER: Depth in Chemistry (Foundation Tier). All Assessment Questions & Mark Scheme [OCR
J258/02]
Exam Resource Summary
The GCSE (9–1) Chemistry B (Twenty First Century Science) June 2025 Foundation Tier Paper (OCR
J258/02) combines the full official examination paper with its detailed mark scheme to create a clear and
structured revision resource. This paper assesses students’ understanding of key chemistry concepts in
depth, including atomic structure, bonding, chemical reactions, energy changes, rates of reaction, the
periodic table, and practical investigation skills. Candidates are expected to apply knowledge to practical
scenarios, interpret data, analyse outcomes, and communicate scientific explanations accurately. By
presenting each question alongside its marking criteria, this merged resource clarifies examiner
expectations, demonstrates the level of analytical and evaluative skills required for top marks, and
supports learners in producing well-structured and precise responses. The integrated format strengthens
revision efficiency, improves exam technique, and prepares students thoroughly for the 2026 OCR GCSE
Chemistry B (Twenty First Century Science) Foundation Tier Depth in Chemistry examination.
OCR is an exempt Charity
Turn over
, 2
1 Fig. 1.1 shows the names and formulae of some acids and alkalis.
Fig. 1.1
Name of compound Formula
Hydrochloric acid HCl
Acids
Sulfuric acid H2SO4
Lithium hydroxide LiOH
Alkalis Sodium hydroxide NaOH
Potassium hydroxide KOH
(a) Write down the name of a compound from Fig. 1.1 to answer the following questions.
(i) Which compound has a formula with 2 atoms?
. ................................................................................................................................................. [1]
(ii) Which alkali reacts with hydrochloric acid to make sodium chloride?
. ................................................................................................................................................. [1]
(iii) Which alkali has the highest relative formula mass?
Use the Periodic Table to help you.
. ................................................................................................................................................. [1]
(iv) Which two compounds can each react with magnesium metal to make hydrogen?
....................................................................... and ..................................................................... [1]
(v) Which compound gives a white precipitate when a few drops are added to dilute barium nitrate?
. ................................................................................................................................................. [1]
(b) Which statements are true and which are false?
Tick (✓) one box in each row.
True False
Acids form hydrogen ions when they dissolve in water.
All neutralisation reactions make water.
Copper does not react with dilute acid.
Titrations give qualitative data.
[3]
© OCR 2025
, 3
(c) A student does a titration to find out how much acid is needed to neutralise 25.0 cm3 aqueous
sodium hydroxide.
They add the aqueous sodium hydroxide to a conical flask.
Aqueous sodium hydroxide
(i) The student adds another substance to the conical flask so that they know when the aqueous
sodium hydroxide is neutralised.
Name this substance.
Describe how the substance shows the student that the aqueous sodium hydroxide has been
neutralised.
Name ................................................................................................................................................
Description .......................................................................................................................................
..........................................................................................................................................................
[2]
(ii) Which other piece of apparatus does the student need to do the titration?
Tick (✓) one box.
Bunsen burner
Burette
Stop clock
Test-tube
Thermometer
[1]
(iii) The student does the titration and then looks at the results of another student.
Explain why the student looks at the results of another student.
..........................................................................................................................................................
. ................................................................................................................................................. [1]
© OCR 2025 Turn over
, 4
2 Several processes can be used to produce drinking water.
Each process has a purpose.
(a) Draw lines to connect each water treatment process with its correct purpose.
Water treatment process Purpose
Aeration Separates pure water from salt water.
Distillation Uses oxygen to break down harmful waste.
Filtration Removes solid impurities.
[2]
(b) Water for drinking is treated with chlorine.
What is the test and expected result for chlorine gas?
Tick (✓) one box in each column.
Test Expected result
Aqueous bromine goes blue
Damp blue litmus paper goes green
Lighted splint goes red then white
[2]
© OCR 2025
PAPER: Depth in Chemistry (Foundation Tier). All Assessment Questions & Mark Scheme [OCR
J258/02]
Exam Resource Summary
The GCSE (9–1) Chemistry B (Twenty First Century Science) June 2025 Foundation Tier Paper (OCR
J258/02) combines the full official examination paper with its detailed mark scheme to create a clear and
structured revision resource. This paper assesses students’ understanding of key chemistry concepts in
depth, including atomic structure, bonding, chemical reactions, energy changes, rates of reaction, the
periodic table, and practical investigation skills. Candidates are expected to apply knowledge to practical
scenarios, interpret data, analyse outcomes, and communicate scientific explanations accurately. By
presenting each question alongside its marking criteria, this merged resource clarifies examiner
expectations, demonstrates the level of analytical and evaluative skills required for top marks, and
supports learners in producing well-structured and precise responses. The integrated format strengthens
revision efficiency, improves exam technique, and prepares students thoroughly for the 2026 OCR GCSE
Chemistry B (Twenty First Century Science) Foundation Tier Depth in Chemistry examination.
OCR is an exempt Charity
Turn over
, 2
1 Fig. 1.1 shows the names and formulae of some acids and alkalis.
Fig. 1.1
Name of compound Formula
Hydrochloric acid HCl
Acids
Sulfuric acid H2SO4
Lithium hydroxide LiOH
Alkalis Sodium hydroxide NaOH
Potassium hydroxide KOH
(a) Write down the name of a compound from Fig. 1.1 to answer the following questions.
(i) Which compound has a formula with 2 atoms?
. ................................................................................................................................................. [1]
(ii) Which alkali reacts with hydrochloric acid to make sodium chloride?
. ................................................................................................................................................. [1]
(iii) Which alkali has the highest relative formula mass?
Use the Periodic Table to help you.
. ................................................................................................................................................. [1]
(iv) Which two compounds can each react with magnesium metal to make hydrogen?
....................................................................... and ..................................................................... [1]
(v) Which compound gives a white precipitate when a few drops are added to dilute barium nitrate?
. ................................................................................................................................................. [1]
(b) Which statements are true and which are false?
Tick (✓) one box in each row.
True False
Acids form hydrogen ions when they dissolve in water.
All neutralisation reactions make water.
Copper does not react with dilute acid.
Titrations give qualitative data.
[3]
© OCR 2025
, 3
(c) A student does a titration to find out how much acid is needed to neutralise 25.0 cm3 aqueous
sodium hydroxide.
They add the aqueous sodium hydroxide to a conical flask.
Aqueous sodium hydroxide
(i) The student adds another substance to the conical flask so that they know when the aqueous
sodium hydroxide is neutralised.
Name this substance.
Describe how the substance shows the student that the aqueous sodium hydroxide has been
neutralised.
Name ................................................................................................................................................
Description .......................................................................................................................................
..........................................................................................................................................................
[2]
(ii) Which other piece of apparatus does the student need to do the titration?
Tick (✓) one box.
Bunsen burner
Burette
Stop clock
Test-tube
Thermometer
[1]
(iii) The student does the titration and then looks at the results of another student.
Explain why the student looks at the results of another student.
..........................................................................................................................................................
. ................................................................................................................................................. [1]
© OCR 2025 Turn over
, 4
2 Several processes can be used to produce drinking water.
Each process has a purpose.
(a) Draw lines to connect each water treatment process with its correct purpose.
Water treatment process Purpose
Aeration Separates pure water from salt water.
Distillation Uses oxygen to break down harmful waste.
Filtration Removes solid impurities.
[2]
(b) Water for drinking is treated with chlorine.
What is the test and expected result for chlorine gas?
Tick (✓) one box in each column.
Test Expected result
Aqueous bromine goes blue
Damp blue litmus paper goes green
Lighted splint goes red then white
[2]
© OCR 2025
