Tuesday 19 May 2026 – Morning
AS Level Chemistry A
H032/02 Depth in chemistry
Time allowed: 1 hour 30 minutes
You must have:
* 2 6 4 6 9 2 8 9 9 6 *
• the Data Sheet for Chemistry A
You can use:
• a scientific or graphical calculator
• an HB pencil
* H 0 3 2 0 2 *
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 70.
• 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.
© Cambridge OCR 2026 [601/5256/4] Cambridge OCR is an exempt Charity
DC (SL/CB) 363552/5 Turn over
, 2
1 The element gallium has a relative atomic mass of 69.7. It is in Group 3 of the periodic table.
(a)
(i) What is meant by the term relative atomic mass?
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..................................................................................................................................................... [2]
(ii) A sample of gallium, with relative atomic mass of 69.7, has two isotopes:
• 39.9% Ga-71
• one other isotope
Calculate the mass number of the other isotope.
Give your answer to the nearest whole number.
Mass number = .......................................................... [2]
(b) Aluminium is in the same group of the periodic table as gallium.
(i) When aluminium reacts with fluorine it forms an ionic compound, Al F3.
Draw a ‘dot-and-cross’ diagram to show the bonding in Al F3.
Show outer electrons only.
[2]
© Cambridge OCR 2026
, 3
(ii) Aluminium chloride, Al Cl 3, has a simple covalent structure.
Al F3 and Al Cl 3 have different melting points and electrical conductivities as shown in the table.
Electrical conductivity
Substance Melting point / °C
of liquid
Al F3 1291 Good
Al Cl 3 190 Poor
Explain the differences in terms of the particles present and the forces between them.
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..........................................................................................................................................................
..................................................................................................................................................... [4]
© Cambridge OCR 2026 Turn over
AS Level Chemistry A
H032/02 Depth in chemistry
Time allowed: 1 hour 30 minutes
You must have:
* 2 6 4 6 9 2 8 9 9 6 *
• the Data Sheet for Chemistry A
You can use:
• a scientific or graphical calculator
• an HB pencil
* H 0 3 2 0 2 *
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 70.
• 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.
© Cambridge OCR 2026 [601/5256/4] Cambridge OCR is an exempt Charity
DC (SL/CB) 363552/5 Turn over
, 2
1 The element gallium has a relative atomic mass of 69.7. It is in Group 3 of the periodic table.
(a)
(i) What is meant by the term relative atomic mass?
..........................................................................................................................................................
..........................................................................................................................................................
..........................................................................................................................................................
..................................................................................................................................................... [2]
(ii) A sample of gallium, with relative atomic mass of 69.7, has two isotopes:
• 39.9% Ga-71
• one other isotope
Calculate the mass number of the other isotope.
Give your answer to the nearest whole number.
Mass number = .......................................................... [2]
(b) Aluminium is in the same group of the periodic table as gallium.
(i) When aluminium reacts with fluorine it forms an ionic compound, Al F3.
Draw a ‘dot-and-cross’ diagram to show the bonding in Al F3.
Show outer electrons only.
[2]
© Cambridge OCR 2026
, 3
(ii) Aluminium chloride, Al Cl 3, has a simple covalent structure.
Al F3 and Al Cl 3 have different melting points and electrical conductivities as shown in the table.
Electrical conductivity
Substance Melting point / °C
of liquid
Al F3 1291 Good
Al Cl 3 190 Poor
Explain the differences in terms of the particles present and the forces between them.
..........................................................................................................................................................
..........................................................................................................................................................
..........................................................................................................................................................
..........................................................................................................................................................
..........................................................................................................................................................
..........................................................................................................................................................
..........................................................................................................................................................
..........................................................................................................................................................
..........................................................................................................................................................
..................................................................................................................................................... [4]
© Cambridge OCR 2026 Turn over
