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Mathematics

Edexcel2023

disproportionation. (3) .................................................................................................................................................................................................................................................................................... .................................................................................................................................................................................................................................................................................... .................................................................................................................................................................................................................................................................................... .................................................................................................................................................................................................................................................................................... .................................................................................................................................................................................................................................................................................... ....................................................................................................................................................................................................................................................................................

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Mathematics

Edexcel2023

2 Equations are not required. (3) .................................................................................................................................................................................................................................................................................... .................................................................................................................................................................................................................................................................................... .................................................................................................................................................................................................................................................................................... .................................................................................................................................................................................................................................................................................... .................................................................................................................................................................................................................................................................................... .................................................................................................................................................................................................................................................................................... (ii) Explain, using information in the table, whether the disproportionation of V2+(aq) into V3+(aq) and V(s) is feasible under standard conditions. (2) .................................................................................................................................................................................................................................................................................... .................................................................................................................................................................................................................................................................................... .................................................................................................................................................................................................................................................................................... .................................................................................................................................................................................................................................................................................... .................................................................................................................................................................................................................................................................................... (Total for Question 3 = 7 marks)

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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 .

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Mathematics

Edexcel2023

3 Ionisation energy

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Mathematics

Edexcel2023

Chemists often use the term ‘orbital’ when considering atomic structure. (a) State what is meant by the term orbital. (2) .................................................................................................................................................................................................................................................................................... .................................................................................................................................................................................................................................................................................... .................................................................................................................................................................................................................................................................................... .................................................................................................................................................................................................................................................................................... .................................................................................................................................................................................................................................................................................... .................................................................................................................................................................................................................................................................................... (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) 

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Mathematics

Edexcel2023

6 When molten, it is suggested that it breaks down as shown. I Cl  ICl+ + ICl–

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Mathematics

Edexcel2023

6 2 4 (i) Draw a labelled diagram of a simple experiment to confirm this dissociation has occurred, stating the positive result. (2) Result .................................................................................................................................................................................................................................................................. (ii) What is the shape of the ICl– ion?

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Mathematics

Edexcel2023

6 I Cl  ICl+ + ICl–

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Mathematics

Edexcel2023

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) 

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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 

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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) 

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Mathematics

Edexcel2023

4 3 complex ion [Cr(H O) ]3+(aq).

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Mathematics

Edexcel2023

6 (i) State the colour of this complex ion. (1) .................................................................................................................................................................................................................................................................................... (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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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

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Mathematics

Edexcel2023

7 2 Equilibrium 2 Cl (aq) + 2e–  2Cl–(aq) Ed = +1.36 V

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Mathematics

Edexcel2023

(4) .................................................................................................................................................................................................................................................................................... .................................................................................................................................................................................................................................................................................... .................................................................................................................................................................................................................................................................................... .................................................................................................................................................................................................................................................................................... .................................................................................................................................................................................................................................................................................... .................................................................................................................................................................................................................................................................................... .................................................................................................................................................................................................................................................................................... .................................................................................................................................................................................................................................................................................... .................................................................................................................................................................................................................................................................................... .................................................................................................................................................................................................................................................................................... .................................................................................................................................................................................................................................................................................... .................................................................................................................................................................................................................................................................................... .................................................................................................................................................................................................................................................................................... .................................................................................................................................................................................................................................................................................... .................................................................................................................................................................................................................................................................................... .................................................................................................................................................................................................................................................................................... .................................................................................................................................................................................................................................................................................... (Total for Question 7 = 13 marks) 

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Mathematics

Edexcel2023

4 by manganate(VII) ions, MnO–(aq).

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Mathematics

Edexcel2023

All quantities are measured in kJ mol–1. –2969 2Ag+(g) + O2–(g) Ag O(s)

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Mathematics

Edexcel2023

+798 +731 × 2 –141.1 –31 O(g) Δ Hd(Ag(s)) × 2 +249.2 at 2Ag(s) + ½O (g)

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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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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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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)

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Mathematics

Edexcel2023

2 • excess potassium iodide solution was then added, forming iodine Mn4+(aq) + 2I–(aq) → Mn2+(aq) + I (aq)

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Mathematics

Edexcel2023

• the liberated iodine was then titrated with sodium thiosulfate solution, Na S O (aq), of concentration 0.00518 mol dm–3

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Mathematics

Edexcel2023

2 3 I (aq) + 2S O2–(aq) → 2I–(aq) + S O2–(aq)

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Mathematics

Edexcel2023

2 3 4 6 • the mean volume of the titre of Na S O (aq) was 34.20 cm3.

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Mathematics

Edexcel2023

2 3 (i) Calculate the concentration of dissolved oxygen in the sample of river water, in g dm–3. (5) 

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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) .................................................................................................................................................................................................................................................................................... .................................................................................................................................................................................................................................................................................... .................................................................................................................................................................................................................................................................................... .................................................................................................................................................................................................................................................................................... .................................................................................................................................................................................................................................................................................... .................................................................................................................................................................................................................................................................................... .................................................................................................................................................................................................................................................................................... .................................................................................................................................................................................................................................................................................... .................................................................................................................................................................................................................................................................................... .................................................................................................................................................................................................................................................................................... (Total for Question 10 = 15 marks) TOTAL FOR PAPER = 90 MARKS 

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Mathematics

Edexcel2022

*P67093RA0232* 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 .

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Mathematics

Edexcel2022

This question is about the elements in Group 2 of the Periodic Table. (a) Magnesium powder is added to a beaker of water containing a few drops of Universal Indicator. The apparatus is set up as shown and allowed to stand for a few days. test tube filled with water water and Universal Indicator filter funnel magnesium powder State two changes that will be seen after a few days. (2) .................................................................................................................................................................................................................................................................................... .................................................................................................................................................................................................................................................................................... .................................................................................................................................................................................................................................................................................... (b) Explain how the trend in the reactivity of the Group 2 elements is determined by their electronic configurations. (3) .................................................................................................................................................................................................................................................................................... .................................................................................................................................................................................................................................................................................... .................................................................................................................................................................................................................................................................................... .................................................................................................................................................................................................................................................................................... .................................................................................................................................................................................................................................................................................... .................................................................................................................................................................................................................................................................................... .................................................................................................................................................................................................................................................................................... .................................................................................................................................................................................................................................................................................... .................................................................................................................................................................................................................................................................................... .................................................................................................................................................................................................................................................................................... 

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Mathematics

Edexcel2022

2 Explain, in terms of electrons, why this is a redox reaction. (2) .................................................................................................................................................................................................................................................................................... .................................................................................................................................................................................................................................................................................... .................................................................................................................................................................................................................................................................................... .................................................................................................................................................................................................................................................................................... .................................................................................................................................................................................................................................................................................... .................................................................................................................................................................................................................................................................................... (d) An experiment was carried out to determine the molar volume of hydrogen at room temperature.

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Mathematics

Edexcel2022

2 Calculate the molar volume of hydrogen from the results of this experiment. Include units in your answer. (2) (Total for Question 2 = 9 marks) 

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Mathematics

Edexcel2022

2 B Br (aq) + 2NaF(aq) → 2NaBr(aq) + F (aq)

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Mathematics

Edexcel2022

2 C Cl (aq) + 2NaBr(aq) → 2NaCl(aq) + Br (aq)

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Mathematics

Edexcel2022

2 D Cl (aq) + 2NaF(aq) → 2NaCl(aq) + F (aq)

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Mathematics

Edexcel2022

2 (c) The halogens can form halide ions during reactions. Complete the electronic configuration of the chloride ion. (1) 1s2 ....................................................................................................................................... 

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Mathematics

Edexcel2022

2HOBr(aq) + 2H+(aq) + 2e–  Br (aq) + 2H O(l) Ed = +1.57 V

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Mathematics

Edexcel2022

2 (i) Explain why the disproportionation of bromine in water is not thermodynamically feasible under standard conditions. Include the overall equation for the disproportionation and its Ed value. cell (3) .................................................................................................................................................................................................................................................................................... .................................................................................................................................................................................................................................................................................... (ii) Bromine disproportionates in water to a small extent at 298 K. Give a possible reason why this reaction occurs. (1) .................................................................................................................................................................................................................................................................................... .................................................................................................................................................................................................................................................................................... .................................................................................................................................................................................................................................................................................... 

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Mathematics

Edexcel2022

though it has fewer electrons in its molecules • the density of ice at 0 °C is less than that of water at 0 °C. Explain these properties. You should include a labelled diagram to show the intermolecular forces between two molecules of water. (6) .................................................................................................................................................................................................................................................................................... .................................................................................................................................................................................................................................................................................... .................................................................................................................................................................................................................................................................................... .................................................................................................................................................................................................................................................................................... .................................................................................................................................................................................................................................................................................... .................................................................................................................................................................................................................................................................................... .................................................................................................................................................................................................................................................................................... .................................................................................................................................................................................................................................................................................... .................................................................................................................................................................................................................................................................................... .................................................................................................................................................................................................................................................................................... .................................................................................................................................................................................................................................................................................... .................................................................................................................................................................................................................................................................................... .................................................................................................................................................................................................................................................................................... 

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Mathematics

Edexcel2022

3 (3) .................................................................................................................................................................................................................................................................................... .................................................................................................................................................................................................................................................................................... .................................................................................................................................................................................................................................................................................... .................................................................................................................................................................................................................................................................................... .................................................................................................................................................................................................................................................................................... .................................................................................................................................................................................................................................................................................... 

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Mathematics

Edexcel2022

3 3 

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Mathematics

Edexcel2022

2 (c) Lead-acid batteries are used as storage cells in some cars. The electrolyte is sulfuric acid, one electrode is lead and the other is lead(IV) oxide, PbO .

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Mathematics

Edexcel2022

As the cell discharges, the lead and the lead(IV) oxide are both converted to solid lead(II) sulfate, PbSO , and the concentration of the sulfuric acid decreases.

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Mathematics

Edexcel2022

7 2 (i) Write the overall equation for the reduction of dichromate(VI) ions to chromium(III) ions by zinc in acid conditions. State symbols are not required. (2) (ii) Calculate Ed for the reaction in (c)(i). cell (1) (iii) Predict whether or not a further reduction of chromium(III) ions to chromium(II) ions will occur. Justify your answer. (1) .................................................................................................................................................................................................................................................................................... .................................................................................................................................................................................................................................................................................... .................................................................................................................................................................................................................................................................................... .................................................................................................................................................................................................................................................................................... 

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Mathematics

Edexcel2022

7 2 Determine, using the experimental data, the brand of nail that was analysed. (5) 

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Mathematics

Edexcel2022

2 B 2H (g) + 2O (g) + 4e– → 4OH – (aq)

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Mathematics

Edexcel2022

2 C 4OH – (aq) → 2H (g) + 2O (g) + 4e–

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Mathematics

Edexcel2022

2 D 2H O(l) → 4H + (aq) + O (g) + 4e–

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Mathematics

Edexcel2021

Ca2+(aq) + 2Br–(aq) Enthalpy change Value / kJ mol–1 enthalpy change of solution of CaBr –73

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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)

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