2025 OCR GCSE Combined Science B (Twenty First Century Science)
J260/06 Chemistry (Higher Tier)
Complete Question paper with Marking Scheme Combined
Monday 19 May 2025 – Morning
GCSE (9–1) Combined Science B
(Twenty First Century Science)
J260/06 Chemistry (Higher Tier)
Time allowed: 1 hour 45 minutes
You must have:
• a ruler (cm/mm)
• the Data Sheet for GCSE (9–1) Combined
Science (Chemistry) B (inside this
document)
You can use:
• an HB pencil
• a scientific or graphical calculator
Please write clearly in black ink. Do not write in the barcodes.
Centre number Candidate number
First name(s)
Last name
INSTRUCTIONS
• Use black ink. You can use an HB pencil, but only for graphs and diagrams.
• Write your answer to each question in the space provided. If you need extra
space use the lined pages at the end of this booklet. The question numbers
must be clearly shown.
• Answer all the questions.
• Where appropriate, your answer should be supported with working.
Marks might be given for using a correct method, even if your answer is
wrong.
INFORMATION
• The total mark for this paper is 95.
• The marks for each question are shown in brackets [ ].
• Quality of extended response will be assessed in questions marked with an
asterisk (*).
• This document has 24 pages.
ADVICE
• Read each question carefully before you start your answer.
,© OCR 2025
OCR is an exempt
[601/8690/2] DC
Charity Turn over
(CE/SW) 353481/5
, 2
1 In the 1800s, Dalton did experiments to help produce a model for the atom.
(a) Later discoveries led to scientists suggesting new models for the atom.
Draw lines to connect each discovery with the model it led to.
Discovery Model
_
_
Electrons are discovered. _
_
_
+− +
− −−
Electrons are in shells. ++ − +
– − +
+ − +−
−
Nucleus is discovered.
[2]
(b) The modern model of the atom consists of electrons, neutrons and protons.
Which statements about the modern model of the atom are true and which
are false? Tick (✓) one box in each row.
True False
Neutrons have a charge of 0.
Protons and electrons are in the nucleus.
Protons and electrons have a relative charge of
–1.
Protons and neutrons have a relative mass of
1.
[3]
© OCR
2025
, 3
(c) The diameter of an atom is 1 × 10–10 m and the diameter of a nucleus is 1.7 × 10–15 m.
Estimate how many times bigger the atom is compared to the nucleus.
Number of times bigger =...............................................[2]
(d) The atomic number and mass number can be used to find the number of protons,
neutrons and electrons in an atom.
The table shows information about an argon atom and a potassium
atom. Complete the table.
Argon atom Potassium atom
Atomic number 18
......................
Mass number 40
......................
Number of electrons 19
......................
Number of neutrons 20
......................
Number of protons 19
......................
[4]
© OCR Turn over
2025
J260/06 Chemistry (Higher Tier)
Complete Question paper with Marking Scheme Combined
Monday 19 May 2025 – Morning
GCSE (9–1) Combined Science B
(Twenty First Century Science)
J260/06 Chemistry (Higher Tier)
Time allowed: 1 hour 45 minutes
You must have:
• a ruler (cm/mm)
• the Data Sheet for GCSE (9–1) Combined
Science (Chemistry) B (inside this
document)
You can use:
• an HB pencil
• a scientific or graphical calculator
Please write clearly in black ink. Do not write in the barcodes.
Centre number Candidate number
First name(s)
Last name
INSTRUCTIONS
• Use black ink. You can use an HB pencil, but only for graphs and diagrams.
• Write your answer to each question in the space provided. If you need extra
space use the lined pages at the end of this booklet. The question numbers
must be clearly shown.
• Answer all the questions.
• Where appropriate, your answer should be supported with working.
Marks might be given for using a correct method, even if your answer is
wrong.
INFORMATION
• The total mark for this paper is 95.
• The marks for each question are shown in brackets [ ].
• Quality of extended response will be assessed in questions marked with an
asterisk (*).
• This document has 24 pages.
ADVICE
• Read each question carefully before you start your answer.
,© OCR 2025
OCR is an exempt
[601/8690/2] DC
Charity Turn over
(CE/SW) 353481/5
, 2
1 In the 1800s, Dalton did experiments to help produce a model for the atom.
(a) Later discoveries led to scientists suggesting new models for the atom.
Draw lines to connect each discovery with the model it led to.
Discovery Model
_
_
Electrons are discovered. _
_
_
+− +
− −−
Electrons are in shells. ++ − +
– − +
+ − +−
−
Nucleus is discovered.
[2]
(b) The modern model of the atom consists of electrons, neutrons and protons.
Which statements about the modern model of the atom are true and which
are false? Tick (✓) one box in each row.
True False
Neutrons have a charge of 0.
Protons and electrons are in the nucleus.
Protons and electrons have a relative charge of
–1.
Protons and neutrons have a relative mass of
1.
[3]
© OCR
2025
, 3
(c) The diameter of an atom is 1 × 10–10 m and the diameter of a nucleus is 1.7 × 10–15 m.
Estimate how many times bigger the atom is compared to the nucleus.
Number of times bigger =...............................................[2]
(d) The atomic number and mass number can be used to find the number of protons,
neutrons and electrons in an atom.
The table shows information about an argon atom and a potassium
atom. Complete the table.
Argon atom Potassium atom
Atomic number 18
......................
Mass number 40
......................
Number of electrons 19
......................
Number of neutrons 20
......................
Number of protons 19
......................
[4]
© OCR Turn over
2025
