GCSE (9–1) Chemistry A (Gateway Science)
J248/04 (Higher Tier)
Time allowed: 1 hour 45 minutes
You must have:
• a ruler (cm/mm)
• the Data Sheet for GCSE (9–1) Chemistry A
(inside this document)
You can use:
• a scientific or graphical calculator
• an HB pencil
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 page 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 90.
• 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 28 pages.
ADVICE
• Read each question carefully before you start your answer.
OCR GCSE Chemistry A (Gateway Science
Higher Tier (J248/04) Question Paper and
Mark Scheme 2026
, 2
Section A
You should spend a maximum of 30 minutes on this section.
Write your answer to each question in the box provided.
1 Which row in the table shows the change in the percentage of each gas in the Earth’s
atmosphere today compared to the Earth’s early atmosphere?
Carbon dioxide Oxygen
A decreased decreased
B decreased increased
C increased decreased
D increased increased
Your answer [1]
© OCR 2025
, 3
2 An iron nail is left in a test tube containing water.
Iron nail
Water
The iron nail rusts.
Which graph shows how the mass of the iron nail changes?
A
Mass
0
0 Time
B
Mass
0
0 Time
C
Mass
0
0 Time
D
Mass
0
0 Time
Your answer [1]
© OCR 2025 Turn over
, 4
3 The alkanes are a homologous series of molecules.
Which statement about different alkane molecules is correct?
A The molecular formula of the molecules differs by CH3.
B The molecules all contain a double bond.
C The molecules all have the same general formula.
D The molecules all have the same physical properties.
Your answer [1]
4 Which row in the table shows a property of a Group 1 metal and of a transition metal?
Group 1 metal Transition metal
A forms white compounds low density
B high melting point conducts electricity
C low density forms coloured compounds
D very reactive low density
Your answer [1]
5 The theoretical yield of a product in a reaction is 71 g.
The actual yield is 60 g.
What is the percentage yield?
A 15.5%
B 18.3%
C 84.5%
D 118.3%
Your answer [1]
© OCR 2025
J248/04 (Higher Tier)
Time allowed: 1 hour 45 minutes
You must have:
• a ruler (cm/mm)
• the Data Sheet for GCSE (9–1) Chemistry A
(inside this document)
You can use:
• a scientific or graphical calculator
• an HB pencil
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 page 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 90.
• 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 28 pages.
ADVICE
• Read each question carefully before you start your answer.
OCR GCSE Chemistry A (Gateway Science
Higher Tier (J248/04) Question Paper and
Mark Scheme 2026
, 2
Section A
You should spend a maximum of 30 minutes on this section.
Write your answer to each question in the box provided.
1 Which row in the table shows the change in the percentage of each gas in the Earth’s
atmosphere today compared to the Earth’s early atmosphere?
Carbon dioxide Oxygen
A decreased decreased
B decreased increased
C increased decreased
D increased increased
Your answer [1]
© OCR 2025
, 3
2 An iron nail is left in a test tube containing water.
Iron nail
Water
The iron nail rusts.
Which graph shows how the mass of the iron nail changes?
A
Mass
0
0 Time
B
Mass
0
0 Time
C
Mass
0
0 Time
D
Mass
0
0 Time
Your answer [1]
© OCR 2025 Turn over
, 4
3 The alkanes are a homologous series of molecules.
Which statement about different alkane molecules is correct?
A The molecular formula of the molecules differs by CH3.
B The molecules all contain a double bond.
C The molecules all have the same general formula.
D The molecules all have the same physical properties.
Your answer [1]
4 Which row in the table shows a property of a Group 1 metal and of a transition metal?
Group 1 metal Transition metal
A forms white compounds low density
B high melting point conducts electricity
C low density forms coloured compounds
D very reactive low density
Your answer [1]
5 The theoretical yield of a product in a reaction is 71 g.
The actual yield is 60 g.
What is the percentage yield?
A 15.5%
B 18.3%
C 84.5%
D 118.3%
Your answer [1]
© OCR 2025
