Cambridge O Level
CHEMISTRY 5070/11
Paper 1 Multiple Choice May/June 2025
1 hour
You must answer on the multiple choice answer sheet.
*2316952197*
You will need: Multiple choice answer sheet
Soft clean eraser
Soft pencil (type B or HB is recommended)
INSTRUCTIONS
There are forty questions on this paper. Answer all questions.
For each question there are four possible answers A, B, C and D. Choose the one you consider correct
and record your choice in soft pencil on the multiple choice answer sheet.
Follow the instructions on the multiple choice answer sheet.
Write in soft pencil.
Write your name, centre number and candidate number on the multiple choice answer sheet in the
spaces provided unless this has been done for you.
Do not use correction fluid.
Do not write on any bar codes.
You may use a calculator.
INFORMATION
The total mark for this paper is 40.
Each correct answer will score one mark.
Any rough working should be done on this question paper.
The Periodic Table is printed in the question paper.
This document has 16 pages. Any blank pages are indicated.
IB25 06_5070_11/3RP
© UCLES 2025 [Turn over
, 2
1 Four gases are listed.
1 CH4
2 NH3
3 CO2
4 N2
What is the order of their rate of diffusion at room temperature and pressure?
slowest fastest
A 1 2 4 3
B 2 1 3 4
C 3 4 2 1
D 4 1 3 2
2 Sodium is added to water and a chemical reaction occurs. Hydrogen and aqueous
sodium hydroxide are produced.
Which row describes the reactants and products in this reaction?
reactants and products reactants and products reactants and products
that are elements that are compounds that are mixtures
A hydrogen water and sodium aqueous sodium hydroxide
B hydrogen and sodium water aqueous sodium hydroxide
C aqueous sodium hydroxide hydrogen and sodium water
D sodium and water aqueous sodium hydroxide hydrogen
© UCLES 2025 5070/11/M/J/25
, 3
3 An atom of element X is shown.
key
= electrons
= protons
= neutrons
Which element is X?
A beryllium
B boron
C carbon
D magnesium
4 Which definition of isotopes is correct?
A atoms of different elements that have the same number of electrons
B atoms of different elements that have the same number of neutrons
C atoms of the same element that have different numbers of electrons
D atoms of the same element that have different numbers of neutrons
5 A pure sample of element X has a relative atomic mass of 51.8.
The sample consists of three isotopes.
The table shows the relative masses and percentage abundances of two of the isotopes.
percentage
relative mass
abundance
of isotope
of isotope
50 40
55 20
What is the relative mass of the third isotope?
A 51 B 52 C 53 D 54
© UCLES 2025 5070/11/M/J/25 [Turn over
CHEMISTRY 5070/11
Paper 1 Multiple Choice May/June 2025
1 hour
You must answer on the multiple choice answer sheet.
*2316952197*
You will need: Multiple choice answer sheet
Soft clean eraser
Soft pencil (type B or HB is recommended)
INSTRUCTIONS
There are forty questions on this paper. Answer all questions.
For each question there are four possible answers A, B, C and D. Choose the one you consider correct
and record your choice in soft pencil on the multiple choice answer sheet.
Follow the instructions on the multiple choice answer sheet.
Write in soft pencil.
Write your name, centre number and candidate number on the multiple choice answer sheet in the
spaces provided unless this has been done for you.
Do not use correction fluid.
Do not write on any bar codes.
You may use a calculator.
INFORMATION
The total mark for this paper is 40.
Each correct answer will score one mark.
Any rough working should be done on this question paper.
The Periodic Table is printed in the question paper.
This document has 16 pages. Any blank pages are indicated.
IB25 06_5070_11/3RP
© UCLES 2025 [Turn over
, 2
1 Four gases are listed.
1 CH4
2 NH3
3 CO2
4 N2
What is the order of their rate of diffusion at room temperature and pressure?
slowest fastest
A 1 2 4 3
B 2 1 3 4
C 3 4 2 1
D 4 1 3 2
2 Sodium is added to water and a chemical reaction occurs. Hydrogen and aqueous
sodium hydroxide are produced.
Which row describes the reactants and products in this reaction?
reactants and products reactants and products reactants and products
that are elements that are compounds that are mixtures
A hydrogen water and sodium aqueous sodium hydroxide
B hydrogen and sodium water aqueous sodium hydroxide
C aqueous sodium hydroxide hydrogen and sodium water
D sodium and water aqueous sodium hydroxide hydrogen
© UCLES 2025 5070/11/M/J/25
, 3
3 An atom of element X is shown.
key
= electrons
= protons
= neutrons
Which element is X?
A beryllium
B boron
C carbon
D magnesium
4 Which definition of isotopes is correct?
A atoms of different elements that have the same number of electrons
B atoms of different elements that have the same number of neutrons
C atoms of the same element that have different numbers of electrons
D atoms of the same element that have different numbers of neutrons
5 A pure sample of element X has a relative atomic mass of 51.8.
The sample consists of three isotopes.
The table shows the relative masses and percentage abundances of two of the isotopes.
percentage
relative mass
abundance
of isotope
of isotope
50 40
55 20
What is the relative mass of the third isotope?
A 51 B 52 C 53 D 54
© UCLES 2025 5070/11/M/J/25 [Turn over
