Candidate surname Other names
Centre Number Candidate Number
Pearson Edexcel International Advanced Level
Thursday 18 January 2024
Afternoon (Time: 1 hour 20 minutes) Paper
reference WCH16/01
Chemistry
International Advanced Level
UNIT 6: Practical Skills in Chemistry II
You must have: Total Marks
Scientific calculator, ruler
Instructions
•• Use black ink or ball‑point pen.
If pencil is used for diagrams/sketches/graphs it must be dark (HB or B).
• Fill in the boxes at the top of this page with your name,
centre number and candidate number.
•• Answer all questions.
Answer the questions in the spaces provided
– there may be more space than you need.
Information
•• The total mark for this paper is 50.
The marks for each question are shown in brackets
– use this as a guide as to how much time to spend on each question.
• You will be assessed on your ability to organise and present information, ideas,
descriptions and arguments clearly and logically, including your use of grammar,
punctuation and spelling.
• A Periodic Table is printed on the back cover of this paper.
Advice
•• Read each question carefully before you start to answer it.
Show all your working in calculations and include units where appropriate.
•• Try to answer every question.
Check your answers if you have time at the end.
Turn over
P74326A
©2024 Pearson Education Ltd.
S:1/1/
*P74326A0116*
, Answer ALL the questions. Write your answers in the spaces provided.
1 A student carried out some tests on four aqueous solutions, labelled A, B, C and D.
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Each solution contained one cation and one anion.
(a) Complete the table.
Test Observation Inference
(i) Dilute aqueous A pale blue precipitate The cation in A is (1)
ammonia was added formed which
drop‑by‑drop to 4 cm3 dissolved to give a ...............................................................
of A until there was no deep blue solution
further change
(ii) Dilute aqueous A white precipitate The formula of the (2)
ammonia was added formed with the first white precipitate is
drop‑by‑drop to 4 cm3 few drops
of B until there was no ...............................................................
further change This precipitate
dissolved in excess The formula of the
ammonia to give a complex ion which
colourless solution forms in the colourless
solution is
...............................................................
(iii) Dilute aqueous The cation in C is Fe3+ (2)
sodium hydroxide was
added drop‑by‑drop to ...............................................................
4 cm3 of C until there
was no further change ...............................................................
...............................................................
...............................................................
(iv) Dilute aqueous An off‑white precipitate The cation in D is (1)
sodium hydroxide was formed which did not
added drop‑by‑drop to dissolve in excess but ...............................................................
4 cm3 of D until there darkened when left
was no further change to stand
(v) Name the type of reaction which results in the darkening of the off‑white
precipitate in (a)(iv).
(1)
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*P74326A0216*
, (b) Adding dilute nitric acid followed by aqueous silver nitrate to A and B resulted in
both forming precipitates.
The student was not certain, but suggested that the anion in A was
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the chloride ion and the anion in B was the bromide ion.
State why the student was not certain and outline a further test which could be
carried out to confirm the presence of both these anions.
(3)
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(c) The student tested for the anion in C by adding acidified barium nitrate solution
and observed a white precipitate.
Give the formula of the compound in solution C.
(1)
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(d) The student researched further tests for the anion present in D.
A test was found which involved the addition of sodium hydroxide solution
followed by aluminium and then heating strongly.
Ammonia gas was given off.
Suggest a possible anion present in D.
(1)
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(Total for Question 1 = 12 marks)
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*P74326A0316* Turn over
, 2 This question is about the identification of four different organic compounds,
W, X, Y and Z. The molecules of each compound contain a total of three
carbon atoms and only one functional group.
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(a) A sample of W gave a positive result with Tollens’ reagent.
Give the positive result and the displayed formula of W.
(2)
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(b) A sample of X produced a sweet‑smelling substance when warmed with
ethanoic acid and a few drops of concentrated sulfuric acid.
(i) Name the functional group in X identified by this test.
(1)
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(ii) There are only two peaks in the 13C NMR spectrum of X.
Draw the displayed formula of X, labelling the carbon environments.
(2)
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*P74326A0416*