6 2 4
(i) Draw a labelled diagram of a simple experiment to confirm this dissociation
has occurred, stating the positive result.
(2)
Result
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(ii) What is the shape of the ICl– ion?
Question
Mathematics
Edexcel2023
7 2
Equilibrium 2
Cl (aq) + 2e– 2Cl–(aq) Ed = +1.36 V
6 2 4
What is the most likely numerical value of K for this equilibrium?
c
(1)
A 1.0 × 106
B 5.0 × 103
C 1.0
D 5.0 × 10–3
(Total for Question 3 = 9 marks)
Question
Mathematics
Edexcel2023
6
I Cl ICl+ + ICl–
Question
Mathematics
Edexcel2023
Chlorine and bromine are elements in Group 7 of the Periodic Table.
Both elements exist in a number of different oxidation numbers and therefore are
involved in many redox reactions.
(a) Write an equation for the reaction between chlorine and cold, dilute aqueous
sodium hydroxide. State symbols are not required.
(1)
(b) Chlorine dioxide reacts with cold, dilute aqueous sodium hydroxide.
The ionic equation for the reaction is:
2ClO (aq) + 2OH−(aq) → ClO –(aq) + ClO –(aq) + H O(l)
2 3 2
Using oxidation numbers, explain why the chlorine in ClO has undergone
Question
Mathematics
Edexcel2023
4 2
colourless brown
(a) The table shows values of ΔG at different temperatures for this reaction.
Temperature / K ΔG / kJ mol–1
350 –4.0
400 –13
450 –22
500 –31
550 –40
(i) Plot a graph of ΔG against temperature.
(2)
ΔG / kJ mol–1
Temperature / K
Question
Mathematics
Edexcel2023
(i) Complete the diagram by adding appropriate species and state symbols to
the empty boxes.
(2)
(ii) Explain why the value for the first electron affinity of oxygen is negative and
the value for the second electron affinity is positive.
(3)
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Question
Mathematics
Edexcel2023
All quantities are measured in kJ mol–1.
–2969
2Ag+(g) + O2–(g) Ag O(s)
Question
Mathematics
Edexcel2023
4 3
complex ion [Cr(H O) ]3+(aq).
Question
Mathematics
Edexcel2023
6
(i) State the colour of this complex ion.
(1)
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(ii) Explain why the aqueous solution of this complex ion has an acidic pH by
considering the interaction between the metal ion and the ligands.
(2)
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Question
Mathematics
Edexcel2023
(ii) Using oxidation numbers, deduce the molar ratio of MnO – to Cl– that would
Question
Mathematics
Edexcel2023
*P71912A0228*
PMT
Answer ALL questions.
Some questions must be answered with a cross in a box . If you change your mind about an
answer, put a line through the box and then mark your new answer with a cross .
Question
Mathematics
Edexcel2023
4 2
colourless brown
(1)
Position of equilibrium Change in colour
A moves to the right mixture gets lighter
B moves to the right mixture gets darker
C moves to the left mixture gets lighter
D moves to the left mixture gets darker
(Total for Question 5 = 7 marks)
Question
Mathematics
Edexcel2023
• the liberated iodine was then titrated with sodium thiosulfate solution,
Na S O (aq), of concentration 0.00518 mol dm–3
Question
Mathematics
Edexcel2023
4
by manganate(VII) ions, MnO–(aq).
Question
Mathematics
Edexcel2023
3
Ionisation
energy
Question
Mathematics
Edexcel2023
2
• the precipitate was then dissolved using excess sulfuric acid, forming
Mn4+(aq) ions
MnO(OH) (s) + 4H+(aq) → Mn4+(aq) + 3H O(l)
Question
Mathematics
Edexcel2023
Show outer shell electrons only.
(1)
(b) The solubility of oxygen in water under standard conditions
is 1.22 × 10–3 mol dm–3.
Comment on this value by considering the type and strength of the
intermolecular forces in
• pure water
• pure oxygen
• a mixture of water and oxygen.
Detailed descriptions of the forces involved are not required.
(4)
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Question
Mathematics
Edexcel2023
2
• excess potassium iodide solution was then added, forming iodine
Mn4+(aq) + 2I–(aq) → Mn2+(aq) + I (aq)
Question
Mathematics
Edexcel2023
Chemists often use the term ‘orbital’ when considering atomic structure.
(a) State what is meant by the term orbital.
(2)
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(b) Draw diagrams to show the shape of an s and a p orbital.
(2)
s orbital p orbital
(c) What is the electronic configuration of a copper atom?
(1)
A [Ar]4s13d10
B [Ar]4s23d9
C [Ar]4s24p13d8
D [Ar]4s24p23d7
(Total for Question 2 = 5 marks)
Question
Mathematics
Edexcel2023
Vanadium is a transition metal that forms ions with several oxidation numbers. Four
of these ions are shown in the table.
Formula of ion Oxidation number of vanadium Colour of ion
V2+ +2 violet
V3+ +3 green
VO2+ +4 blue
VO + +5 yellow
Question
Mathematics
Edexcel2023
2 3
I (aq) + 2S O2–(aq) → 2I–(aq) + S O2–(aq)
Question
Mathematics
Edexcel2023
2 3 4 6
• the mean volume of the titre of Na S O (aq) was 34.20 cm3.
Question
Mathematics
Edexcel2023
2 3
(i) Calculate the concentration of dissolved oxygen in the sample of river water,
in g dm–3.
(5)
Question
Mathematics
Edexcel2023
2
B Mn3+(aq) + e– Mn2+(aq) +1.51
Explain why Mn3+ ions are unstable in aqueous solution.
Include an equation and the type of reaction that occurs.
(4)
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(Total for Question 10 = 15 marks)
TOTAL FOR PAPER = 90 MARKS
Question
Mathematics
Edexcel2023
7
agent made the statement shown.
‘Standard electrode potential data shows that it is never feasible
for a 1.00 mol dm–3 solution of potassium dichromate(VI) to oxidise
the chloride ions in hydrochloric acid.’
Comment on this statement using the data and equilibria shown.
Equilibrium 1
Cr O2–(aq) + 14H+(aq) + 6e– 2Cr3+(aq) + 7H O(l) Ed = +1.33 V
Question
Mathematics
Edexcel2023
6
When molten, it is suggested that it breaks down as shown.
I Cl ICl+ + ICl–
Question
Mathematics
Edexcel2022
100 mol dm–3 aqueous sodium carbonate and the pH is measured.
The titration curve is shown.
Question
Mathematics
Edexcel2022
035 g of magnesium was added to excess hydrochloric acid and
Question
Mathematics
Edexcel2022
0.11 × 10–14
Question
Mathematics
Edexcel2022
This question is about chromium and some of its compounds.
(a) The common oxidation numbers of chromium are +2, +3 and +6.
Give a reason, in terms of ionisation energies, why chromium can show variable
oxidation numbers.
(1)
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(b) The bonding in chromate(VI) ions, CrO2–, is similar to that in sulfate(VI) ions, SO2–.
Question
Mathematics
Edexcel2022
10 20 30 40 50
Volume HCl(aq) / cm3
The reaction takes place in two steps.
The equation for the reaction taking place in the first step is
Na CO (aq) + HCl(aq) → NaHCO (aq) + NaCl(aq)
MgO(s) 26.9
(1)
A +210.8
B –210.8
C +216.6
D –216.6
(Total for Question 6 = 5 marks)
Question
Mathematics
Edexcel2021
Substance Standard molar entropy, Sd / J K–1 mol–1
Mg(s) 32.7
O (g) 205.0
Question
Mathematics
Edexcel2021
2 4 2 3 2
(i) Give two reasons why you would expect ΔSd to be positive.
system
(2)
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(ii) Explain why the wooden block is lifted up by the flask.
(2)
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Question
Mathematics
Edexcel2021
*P65463A01228*
PPMMTT
(ii) Give a reason why bond enthalpy values are always positive.
(1)
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(b) Sodium chlorate(I) is a bleaching agent.
(i) Sodium chlorate(I) can be made by the reaction of chlorine with
sodium hydroxide.
Show, by using oxidation numbers, that this reaction is disproportionation.
2NaOH + Cl → NaClO + NaCl + H O
Question
Mathematics
Edexcel2021
4 5
(3)
Question
Mathematics
Edexcel2021
2
A Pt B Pt
H O Cl Cl OH
Question
Mathematics
Edexcel2021
2
(2)
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(ii) A different bleaching agent can be made by the reaction of chlorine with
sodium hydroxide under different conditions.
Balance this equation.
NaOH + Cl → NaClO + NaCl + H O
............ ............ 2 3 ............ ............ 2
(1)
(iii) What conditions are required for the reaction in (b)(ii)?
(1)
A cold and dilute alkali
B cold and concentrated alkali
C hot alkali
D excess chlorine
Question
Mathematics
Edexcel2021
Barium ions can be identified by their flame colour.
(a) Which of the following should be used for a flame test on barium carbonate?
(1)
A iron wire and water
B iron wire and concentrated hydrochloric acid
C nichrome wire and water
D nichrome wire and concentrated hydrochloric acid
(b) What colour do barium ions give in a flame test?
(1)
A green
B lilac
C red
D yellow
(c) A flame test was carried out on a mixture of barium chloride and magnesium chloride.
How does the presence of magnesium ions affect the appearance of the flame colour
of barium ions?
(1)
A the colour is more intense
B a bright white colour completely masks the barium colour
C there is no change
D the barium colour is decreased by the white magnesium flame colour
(Total for Question 2 = 3 marks)
Question
Mathematics
Edexcel2021
*P65463A0228*
PPMMTT
Answer ALL questions.
Some questions must be answered with a cross in a box .
If you change your mind about an answer, put a line through the box
and then mark your new answer with a cross .
Question
Mathematics
Edexcel2021
enthalpy change of hydration of Ca2+ –1577
enthalpy change of hydration of Br– –336
Calculate the lattice energy of calcium bromide.
(2)
(Total for Question 9 = 12 marks)