Oxford Cambridge and RSA
*1327893624*
Tuesday 14 May 2025 – Morning
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 70.
• The marks for each question are shown in brackets [ ].
• This document has 24 pages.
ADVICE
• Read each question carefully before you start your answer.
© OCR 2024 [601/5256/4] DC (CJ/SW) 334105/4
OCR is an exempt Charity
Turn over
, 2
SECTION A
You should spend a maximum of 25 minutes on this section.
Write your answer to each question in the box provided.
1 Which diagram shows a p-orbital?
A
B
C
D
Your answer
2 Which row shows the atomic structure of 25Mg2+?
Protons Neutrons Electrons
A 10 12 13
B 10 15 12
C 12 13 10
D 12 13 14
Your answer [1] 3 A nitrogen oxide contains 36.84% of nitrogen by
mass.
What is the empirical formula of the nitrogen oxide?
A NO
B NO2
C N2O
D N2O3
Your answer
4 Carbon monoxide reacts with oxygen to form carbon dioxide:
© OCR 2024
, 3
2CO(g) + O2(g) 2CO2(g)
Which volumes of CO(g) and O2(g) produce the largest volume of CO2(g)?
All gas volumes are measured at RTP.
A 1.00 dm3 CO and 4.00 dm3 O2
B 2.00 dm3 CO and 3.00 dm3 O2
C 3.00 dm3 CO and 2.00 dm3 O2
D 4.00 dm3 CO and 1.00 dm3 O2
Your answer
5 Which reaction produces a product with linear molecules?
A 2B + 3F
2
B C + O2
C 2H2 + 2 O
D N2 + 2 3H
Your answer [1] 6 Which statement about the periodic table is
not correct?
A Elements in the same group have similar chemical properties.
B The elements are ordered by increasing atomic mass.
C The elements are ordered by increasing atomic number.
D There is a repeating trend of physical and chemical properties across the
periods.
Your answer
7 Group 2 compounds can be used in agriculture to neutralise acid soils and in
medicine to treat indigestion.
Which Group 2 compound is not suitable for either use?
A Mg(OH)2
© OCR 2024 Turn over
, 4
B MgSO4
C CaCO3
D CaO
Your answer
8 In the UK, water companies typically treat drinking water with chlorine gas at a
concentration of
0.500 mg dm–3 or less.
Which statement about UK drinking water is correct?
A Chlorine in drinking water can catalyse the breakdown of ozone.
B Chlorine may form toxic chlorinated hydrocarbons.
C Drinking water with a chlorine gas concentration of 0.500 mg dm –3 contains 2.12
× 1018 chlorine molecules in each dm3.
D In hot weather, chlorine can vaporise from drinking water to cause global
warming.
Your answer [1] 9 Which reaction does not show disproportionation of
chlorine?
l l
A MnO2 + 4HCl MnC 2 +C 2 + 2H2O
B Cl 2 + H2O HCl + HCl O
C 2Cl O2 + 2NaOH NaCl O2 + NaCl O3 + H2O
D 2NaOH + Cl 2 NaCl + NaCl O + H2O
Your answer
10 An unknown compound is tested to identify whether it contains sulfate, carbonate or
halide ions.
What is the correct sequence of tests required?
A carbonate, halide, sulfate
B carbonate, sulfate, halide
C halide, carbonate, sulfate
© OCR 2024
*1327893624*
Tuesday 14 May 2025 – Morning
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 70.
• The marks for each question are shown in brackets [ ].
• This document has 24 pages.
ADVICE
• Read each question carefully before you start your answer.
© OCR 2024 [601/5256/4] DC (CJ/SW) 334105/4
OCR is an exempt Charity
Turn over
, 2
SECTION A
You should spend a maximum of 25 minutes on this section.
Write your answer to each question in the box provided.
1 Which diagram shows a p-orbital?
A
B
C
D
Your answer
2 Which row shows the atomic structure of 25Mg2+?
Protons Neutrons Electrons
A 10 12 13
B 10 15 12
C 12 13 10
D 12 13 14
Your answer [1] 3 A nitrogen oxide contains 36.84% of nitrogen by
mass.
What is the empirical formula of the nitrogen oxide?
A NO
B NO2
C N2O
D N2O3
Your answer
4 Carbon monoxide reacts with oxygen to form carbon dioxide:
© OCR 2024
, 3
2CO(g) + O2(g) 2CO2(g)
Which volumes of CO(g) and O2(g) produce the largest volume of CO2(g)?
All gas volumes are measured at RTP.
A 1.00 dm3 CO and 4.00 dm3 O2
B 2.00 dm3 CO and 3.00 dm3 O2
C 3.00 dm3 CO and 2.00 dm3 O2
D 4.00 dm3 CO and 1.00 dm3 O2
Your answer
5 Which reaction produces a product with linear molecules?
A 2B + 3F
2
B C + O2
C 2H2 + 2 O
D N2 + 2 3H
Your answer [1] 6 Which statement about the periodic table is
not correct?
A Elements in the same group have similar chemical properties.
B The elements are ordered by increasing atomic mass.
C The elements are ordered by increasing atomic number.
D There is a repeating trend of physical and chemical properties across the
periods.
Your answer
7 Group 2 compounds can be used in agriculture to neutralise acid soils and in
medicine to treat indigestion.
Which Group 2 compound is not suitable for either use?
A Mg(OH)2
© OCR 2024 Turn over
, 4
B MgSO4
C CaCO3
D CaO
Your answer
8 In the UK, water companies typically treat drinking water with chlorine gas at a
concentration of
0.500 mg dm–3 or less.
Which statement about UK drinking water is correct?
A Chlorine in drinking water can catalyse the breakdown of ozone.
B Chlorine may form toxic chlorinated hydrocarbons.
C Drinking water with a chlorine gas concentration of 0.500 mg dm –3 contains 2.12
× 1018 chlorine molecules in each dm3.
D In hot weather, chlorine can vaporise from drinking water to cause global
warming.
Your answer [1] 9 Which reaction does not show disproportionation of
chlorine?
l l
A MnO2 + 4HCl MnC 2 +C 2 + 2H2O
B Cl 2 + H2O HCl + HCl O
C 2Cl O2 + 2NaOH NaCl O2 + NaCl O3 + H2O
D 2NaOH + Cl 2 NaCl + NaCl O + H2O
Your answer
10 An unknown compound is tested to identify whether it contains sulfate, carbonate or
halide ions.
What is the correct sequence of tests required?
A carbonate, halide, sulfate
B carbonate, sulfate, halide
C halide, carbonate, sulfate
© OCR 2024
