Monday 15 June 2026 – Morning
A Level Chemistry B (Salters)
H433/03 Practical skills in chemistry
Time allowed: 1 hour 30 minutes
You must have:
* 2 6 7 0 1 0 2 8 6 7 *
• the Practical Insert (inside this document)
• the Data Sheet for Chemistry B
You can use:
• a scientific or graphical calculator
• an HB pencil
* H 4 3 3 0 3 *
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 60.
• 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 16 pages.
ADVICE
• Read each question carefully before you start your answer.
© Cambridge OCR 2026 [601/5371/4] Cambridge OCR is an exempt Charity
DC (SL/SG) 360659/6 Turn over
for more:
, 2
1 Students carry out an experimental procedure to make aspirin by the reaction shown in
equation 1.1.
Equation 1.1
O OH O OH
O O O
OH + O CH3
+
CH3 O CH3 CH3 OH
O
salicylic acid aspirin
(a) Name two functional groups in aspirin, apart from the benzene ring.
Functional group 1 ...........................................................................................................................
Functional group 2 ...........................................................................................................................
[2]
© Cambridge OCR 2026
for more:
, 3
(b) The students prepare impure solid aspirin by the reaction shown in equation 1.1.
(i) Describe how the aspirin is collected from the reaction mixture, and how soluble impurities
are removed.
..........................................................................................................................................................
..........................................................................................................................................................
..........................................................................................................................................................
..................................................................................................................................................... [2]
(ii) The students recrystallise their sample and check the purity of their aspirin by taking its
melting point.
How would the melting point of impure aspirin differ compared to that of a pure sample?
..........................................................................................................................................................
..................................................................................................................................................... [1]
(iii) The students start with 5.0 g of salicylic acid (Mr = 138) and obtain 2.4 g of aspirin (Mr = 180).
Calculate the percentage yield of the aspirin obtained.
Give your answer to an appropriate number of significant figures.
% yield = ....................................................... % [2]
© Cambridge OCR 2026 Turn over
for more:
A Level Chemistry B (Salters)
H433/03 Practical skills in chemistry
Time allowed: 1 hour 30 minutes
You must have:
* 2 6 7 0 1 0 2 8 6 7 *
• the Practical Insert (inside this document)
• the Data Sheet for Chemistry B
You can use:
• a scientific or graphical calculator
• an HB pencil
* H 4 3 3 0 3 *
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 60.
• 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 16 pages.
ADVICE
• Read each question carefully before you start your answer.
© Cambridge OCR 2026 [601/5371/4] Cambridge OCR is an exempt Charity
DC (SL/SG) 360659/6 Turn over
for more:
, 2
1 Students carry out an experimental procedure to make aspirin by the reaction shown in
equation 1.1.
Equation 1.1
O OH O OH
O O O
OH + O CH3
+
CH3 O CH3 CH3 OH
O
salicylic acid aspirin
(a) Name two functional groups in aspirin, apart from the benzene ring.
Functional group 1 ...........................................................................................................................
Functional group 2 ...........................................................................................................................
[2]
© Cambridge OCR 2026
for more:
, 3
(b) The students prepare impure solid aspirin by the reaction shown in equation 1.1.
(i) Describe how the aspirin is collected from the reaction mixture, and how soluble impurities
are removed.
..........................................................................................................................................................
..........................................................................................................................................................
..........................................................................................................................................................
..................................................................................................................................................... [2]
(ii) The students recrystallise their sample and check the purity of their aspirin by taking its
melting point.
How would the melting point of impure aspirin differ compared to that of a pure sample?
..........................................................................................................................................................
..................................................................................................................................................... [1]
(iii) The students start with 5.0 g of salicylic acid (Mr = 138) and obtain 2.4 g of aspirin (Mr = 180).
Calculate the percentage yield of the aspirin obtained.
Give your answer to an appropriate number of significant figures.
% yield = ....................................................... % [2]
© Cambridge OCR 2026 Turn over
for more:
