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Physics

CAIE2024

V / V OUT

Question

Physics

CAIE2024

BI Hall voltage V = H ntq alternating current/voltage x = x sin ωt

Question

Physics

CAIE2024

V / V OUT

Question

Physics

CAIE2024

BI Hall voltage V = H ntq alternating current/voltage x = x sin ωt

Question

Physics

CAIE2024

(a) (i) State what is meant by rectification of an alternating voltage. ........................................................................................................................................... ..................................................................................................................................... [1] (ii) State the difference between half-wave rectification and full-wave rectification. ........................................................................................................................................... ........................................................................................................................................... ..................................................................................................................................... [2] (b) (i) Complete Fig. 6.1 to show a circuit that produces half-wave rectification of an alternating input voltage V to produce output voltage V across the resistor R. IN OUT V C R V IN OUT Fig. 6.1 [2] (ii) State the purpose of the capacitor C in the circuit of Fig. 6.1. ........................................................................................................................................... ..................................................................................................................................... [1] (c) The input voltage V in Fig. 6.1 is a square wave. Fig. 6.2 shows the variation of V with IN IN time t. +12 V / V IN

Question

Biology

CAIE2024

D [4] (c) Lambert‑Eaton myasthenic syndrome (LEMS) is a rare disorder of the neuromuscular junction. A person with LEMS produces antibodies that bind to the voltage‑gated calcium channels on the presynaptic knob. One symptom of LEMS is weaker muscle contraction. Suggest and explain why LEMS leads to weaker muscle contraction. ................................................................................................................................................... ................................................................................................................................................... ................................................................................................................................................... ................................................................................................................................................... ................................................................................................................................................... ................................................................................................................................................... ................................................................................................................................................... ................................................................................................................................................... ................................................................................................................................................... ............................................................................................................................................. [4] [Total: 11] © UCLES 2024 (cid:300) (cid:300) (cid:207) (cid:224) (cid:266) (cid:202) (cid:190) (cid:243) (cid:288) (cid:215) (cid:180) (cid:294) (cid:237) (cid:242) (cid:200) (cid:273) (cid:245) (cid:220) (cid:207) (cid:257) (cid:298) (cid:252) (cid:197) (cid:292) (cid:266) (cid:283) (cid:223) (cid:274) (cid:251) (cid:292) (cid:183) (cid:179) (cid:258) (cid:277) (cid:215) (cid:258) 9700/42/O/N/24 [Turn over (cid:293)(cid:181)(cid:181)(cid:213)(cid:245)(cid:245)(cid:197)(cid:181)(cid:181)(cid:293)(cid:261)(cid:197)(cid:197)(cid:181)(cid:229)(cid:213)(cid:261)(cid:213) NIGRAM SIHT NI ETIRW TON OD NIGRAM SIHT NI ETIRW TON OD NIGRAM SIHT NI ETIRW TON OD NIGRAM SIHT NI ETIRW TON OD NIGRAM SIHT NI ETIRW TON OD PMT * 0000800000020 *

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Physics

CAIE2024

BI Hall voltage V = H ntq alternating current/voltage x = x sin ωt

Question

Physics

CAIE2024

Question

Physics

CAIE2023

A battery of e.m.f. 12 V and internal resistance 0.5 Ω is connected to an external resistor of 4.5 Ω. (a) Calculate the current in the circuit. (b) Calculate the terminal potential difference of the battery. (c) Calculate the power dissipated in the external resistor. (d) State and explain what happens to the terminal p.d. as the external resistance is decreased.

[7 marks]

Physics

CAIE2023

at B, voltage = V

Question

Physics

CAIE2023

2 alternating current/voltage x = x sinωt o radioactive decay x = x exp(-λt) o

Question

Physics

CAIE2023

For Examiner’s Use The thermistor is held in a water bath at a temperature of 15°C. (i) Determine the voltage

Question

Physics

Edexcel2023

V / V

Question

Physics

CAIE2023

at A, voltage = V

Question

Physics

CAIE2023

at the output of the operational amplifier. voltage = V [4] (ii) State which LED is emitting light. [1] (c) Describe and explain what is observed as the temperature of the thermistor is raised from 15°C to 100°C. [2] © UCLES 2005 9702/04/SPECIMEN PAPER [Turn over PPPMMMTTT For

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

3 Ionisation energy

Question

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) 

Question

Mathematics

Edexcel2023

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

Question

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?

Question

Mathematics

Edexcel2023

6 I Cl  ICl+ + ICl–

Question

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) 

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

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

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

Question

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) .................................................................................................................................................................................................................................................................................... .................................................................................................................................................................................................................................................................................... .................................................................................................................................................................................................................................................................................... .................................................................................................................................................................................................................................................................................... .................................................................................................................................................................................................................................................................................... .................................................................................................................................................................................................................................................................................... 

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

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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).

Question

Mathematics

Edexcel2023

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

Question

Mathematics

Edexcel2023

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

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) .................................................................................................................................................................................................................................................................................... .................................................................................................................................................................................................................................................................................... .................................................................................................................................................................................................................................................................................... .................................................................................................................................................................................................................................................................................... .................................................................................................................................................................................................................................................................................... .................................................................................................................................................................................................................................................................................... .................................................................................................................................................................................................................................................................................... .................................................................................................................................................................................................................................................................................... .................................................................................................................................................................................................................................................................................... .................................................................................................................................................................................................................................................................................... 

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) .................................................................................................................................................................................................................................................................................... .................................................................................................................................................................................................................................................................................... .................................................................................................................................................................................................................................................................................... .................................................................................................................................................................................................................................................................................... .................................................................................................................................................................................................................................................................................... .................................................................................................................................................................................................................................................................................... .................................................................................................................................................................................................................................................................................... .................................................................................................................................................................................................................................................................................... .................................................................................................................................................................................................................................................................................... .................................................................................................................................................................................................................................................................................... .................................................................................................................................................................................................................................................................................... 

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

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

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

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) 

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

Question

Physics

Edexcel2022

V / V out

Question

Mathematics

Edexcel2022

*P67093RA02732* Turn over PMT (b) A fuel cell produces a voltage from the reaction between a fuel and oxygen. The reaction occurring at one electrode in a methanol fuel cell is CH OH(g) + H O(l) → HCOOH(aq) + 4H + (aq) + 4e–

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Physics

CAIE2022

V/ V

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Mathematics

Edexcel2018

+520 Li+(g) + F−(g) Li(g) + ½F (g)

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Mathematics

Edexcel2018

+159 Li(s) + ½F (g)

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Mathematics

Edexcel2018

The equilibrium constant, K , for this reaction is c K = [Mg2+(aq)][OH−(aq)]2 c (i) Give a reason why the magnesium hydroxide is not included in the expression for K . c (1) ..................................................................................................................................................................................................................................................................................... ..................................................................................................................................................................................................................................................................................... ..................................................................................................................................................................................................................................................................................... ..................................................................................................................................................................................................................................................................................... (ii) Give the units for K . c (1)

Question

Mathematics

Edexcel2018

∆ H (Mg2+(aq)) −1920 hyd ∆ H (OH−(aq)) −460 hyd (2) (iv) Which graph shows the change in the concentration of the Mg2+(aq) ions when some solid magnesium hydroxide is shaken with water and left to reach equilibrium? (1) [Mg2+(aq)] [Mg2+(aq)] A /mol dm−3 B /mol dm−3 Time Time [Mg2+(aq)] [Mg2+(aq)] C /mol dm−3 D /mol dm−3 Time Time

Question

Mathematics

Edexcel2018

(4) Magnesium sulfate solution ..................................................................................................................................................................................................................................................................................... ..................................................................................................................................................................................................................................................................................... ..................................................................................................................................................................................................................................................................................... ..................................................................................................................................................................................................................................................................................... ..................................................................................................................................................................................................................................................................................... ..................................................................................................................................................................................................................................................................................... Dilute hydrochloric acid ..................................................................................................................................................................................................................................................................................... ..................................................................................................................................................................................................................................................................................... ..................................................................................................................................................................................................................................................................................... ..................................................................................................................................................................................................................................................................................... ..................................................................................................................................................................................................................................................................................... ..................................................................................................................................................................................................................................................................................... (Total for Question 6 = 10 marks)

Question

Mathematics

Edexcel2018

4 7 2 hydrochloric acid. Write the equation for this reaction. State symbols are not required. (1) (b) The formula of boric acid can also be written as B(OH) .

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