Exercise 1 — IGCSE 0653 May/Jun 2023 Paper 33 Q2
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thermometer
Cambridge IGCSE·Combined Sciences 0653·Chemistry
Organic Chemistry
Key knowledge — Organic Chemistry
Formulas & equations
Combustion of alkane: CₙH₂ₙ₊₂ + O₂ → CO₂ + H₂OAddition of H₂ to alkene: CₙH₂ₙ + H₂ → CₙH₂ₙ₊₂ (hydrogenation)Fermentation: C₆H₁₂O₆ → 2C₂H₅OH + 2CO₂ (ethanol production)Esterification: alcohol + carboxylic acid ⇌ ester + water (concentrated H₂SO₄ catalyst)
Key facts & rules
- Alkanes: saturated (only C−C single bonds). General formula CₙH₂ₙ₊₂. Methane (CH₄), ethane (C₂H₆), propane, butane.
- Alkenes: unsaturated (contain C=C double bond). General formula CₙH₂ₙ. Ethene (C₂H₄), propene.
- Test for alkene: bromine water → decolourises (goes from orange to colourless).
- Cracking: long-chain alkanes → shorter alkanes + alkenes (thermal or catalytic cracking).
- Addition polymerisation: alkene monomers → polymer (e.g. ethene → poly(ethene)).
- Fractional distillation of crude oil: different chain lengths have different boiling points — separated by size.
IGCSE Chemistry — Organic Chemistry
116 Cambridge IGCSE 0653 Combined Sciences past paper questions on organic chemistry, across Theory, Multiple Choice and Alternative to Practical.
About Organic Chemistry on IGCSE 0653
Organic chemistry focuses on carbon compounds. Alkanes are saturated hydrocarbons from crude oil; alkenes are unsaturated and undergo addition reactions. Polymers, ethanol and esters are important organic products.
What's covered:
- Crude oil and fractional distillation
- Alkanes: structure, combustion, substitution
- Alkenes: structure, addition reactions, test with bromine
- Cracking of hydrocarbons
- Addition polymerisation
- Ethanol: fermentation and from ethene
- Esterification
Theory
Organic Chemistry — Core5 · Paper 3
Exercise 2 — IGCSE 0653 May/Jun 2023 Paper 32 Q8
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methane + oxygen carbon dioxide + water
Exercise 3 — IGCSE 0653 May/Jun 2024 Paper 31 Q5
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fractional distillation (circled)
Exercise 4 — IGCSE 0653 Oct/Nov 2023 Paper 32 Q5
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fractional distillation
Exercise 5 — IGCSE 0653 Oct/Nov 2023 Paper 33 Q5
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fractional distillation
Organic Chemistry — Extended7 · Paper 4
Exercise 1 — IGCSE 0653 Mar 2023 Paper 42 Q8
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alkane
Exercise 2 — IGCSE 0653 May/Jun 2023 Paper 42 Q8
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decane and pentane
Exercise 3 — IGCSE 0653 May/Jun 2023 Paper 43 Q8
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ethene and butene
Exercise 4 — IGCSE 0653 May/Jun 2024 Paper 41 Q8
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cracking
Exercise 5 — IGCSE 0653 May/Jun 2025 Paper 41 Q5
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red-brown
Exercise 6 — IGCSE 0653 May/Jun 2025 Paper 43 Q5
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bromine
Exercise 7 — IGCSE 0653 Oct/Nov 2023 Paper 43 Q8
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C H
Multiple choice
Organic Chemistry — Core MCQ68 · Paper 1
Question 1 — IGCSE 0653 Mar 2023 Paper 12 Q21
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Correct answer: A
Question 2 — IGCSE 0653 Mar 2023 Paper 12 Q22
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Correct answer: D
Question 3 — IGCSE 0653 Mar 2023 Paper 12 Q23
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Correct answer: C
Question 4 — IGCSE 0653 Mar 2023 Paper 12 Q24
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Correct answer: D
Question 5 — IGCSE 0653 Mar 2023 Paper 12 Q25
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Correct answer: A
Question 6 — IGCSE 0653 Mar 2023 Paper 12 Q26
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Correct answer: B
Question 7 — IGCSE 0653 Mar 2023 Paper 12 Q27
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Correct answer: A
Question 8 — IGCSE 0653 Mar 2023 Paper 12 Q28
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Correct answer: D
Question 9 — IGCSE 0653 Mar 2023 Paper 12 Q29
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Correct answer: D
Question 10 — IGCSE 0653 Mar 2023 Paper 12 Q30
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Correct answer: A
Question 11 — IGCSE 0653 Mar 2025 Paper 12 Q14
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Correct answer: D
Question 12 — IGCSE 0653 Mar 2025 Paper 12 Q15
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Correct answer: B
Question 13 — IGCSE 0653 Mar 2025 Paper 12 Q16
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Correct answer: C
Question 14 — IGCSE 0653 Mar 2025 Paper 12 Q17
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Correct answer: B
Question 15 — IGCSE 0653 Mar 2025 Paper 12 Q21
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Correct answer: D
Question 16 — IGCSE 0653 Mar 2025 Paper 12 Q22
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Correct answer: A
Question 17 — IGCSE 0653 Mar 2025 Paper 12 Q23
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Correct answer: B
Question 18 — IGCSE 0653 Mar 2025 Paper 12 Q24
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Correct answer: A
Question 19 — IGCSE 0653 Mar 2025 Paper 12 Q25
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Correct answer: B
Question 20 — IGCSE 0653 May/Jun 2023 Paper 11 Q26
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Correct answer: C
Question 21 — IGCSE 0653 May/Jun 2023 Paper 11 Q27
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Correct answer: A
Question 22 — IGCSE 0653 May/Jun 2023 Paper 11 Q28
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Correct answer: B
Question 23 — IGCSE 0653 May/Jun 2023 Paper 11 Q29
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Correct answer: D
Question 24 — IGCSE 0653 May/Jun 2024 Paper 12 Q17
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Correct answer: B
Question 25 — IGCSE 0653 May/Jun 2024 Paper 12 Q18
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Correct answer: D
Question 26 — IGCSE 0653 May/Jun 2024 Paper 12 Q19
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Correct answer: D
Question 27 — IGCSE 0653 May/Jun 2024 Paper 12 Q20
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Correct answer: A
Question 28 — IGCSE 0653 May/Jun 2024 Paper 11 Q21
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Correct answer: D
Question 29 — IGCSE 0653 May/Jun 2024 Paper 12 Q21
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Correct answer: C
Question 30 — IGCSE 0653 May/Jun 2024 Paper 11 Q22
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Correct answer: D
Question 31 — IGCSE 0653 May/Jun 2024 Paper 11 Q23
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Correct answer: C
Question 32 — IGCSE 0653 May/Jun 2024 Paper 11 Q24
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Correct answer: C
Question 33 — IGCSE 0653 May/Jun 2024 Paper 11 Q25
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Correct answer: A
Question 34 — IGCSE 0653 May/Jun 2024 Paper 12 Q25
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Correct answer: C
Question 35 — IGCSE 0653 May/Jun 2024 Paper 11 Q26
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Correct answer: C
Question 36 — IGCSE 0653 May/Jun 2024 Paper 12 Q26
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Correct answer: B
Question 37 — IGCSE 0653 May/Jun 2024 Paper 11 Q27
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Correct answer: B
Question 38 — IGCSE 0653 May/Jun 2024 Paper 12 Q27
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Correct answer: C
Question 39 — IGCSE 0653 May/Jun 2024 Paper 11 Q28
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Correct answer: D
Question 40 — IGCSE 0653 May/Jun 2024 Paper 12 Q28
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Correct answer: D
Question 41 — IGCSE 0653 May/Jun 2024 Paper 12 Q29
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Correct answer: B
Question 42 — IGCSE 0653 May/Jun 2025 Paper 11 Q17
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Correct answer: B
Question 43 — IGCSE 0653 May/Jun 2025 Paper 11 Q18
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Correct answer: A
Question 44 — IGCSE 0653 May/Jun 2025 Paper 11 Q19
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Correct answer: D
Question 45 — IGCSE 0653 Oct/Nov 2023 Paper 12 Q22
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Correct answer: C
Question 46 — IGCSE 0653 Oct/Nov 2023 Paper 13 Q22
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Correct answer: C
Question 47 — IGCSE 0653 Oct/Nov 2023 Paper 12 Q23
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Correct answer: C
Question 48 — IGCSE 0653 Oct/Nov 2023 Paper 13 Q23
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Correct answer: C
Question 49 — IGCSE 0653 Oct/Nov 2023 Paper 12 Q24
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Correct answer: A
Question 50 — IGCSE 0653 Oct/Nov 2023 Paper 13 Q24
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Correct answer: A
Question 51 — IGCSE 0653 Oct/Nov 2023 Paper 12 Q25
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Correct answer: A
Question 52 — IGCSE 0653 Oct/Nov 2023 Paper 13 Q25
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Correct answer: A
Question 53 — IGCSE 0653 Oct/Nov 2023 Paper 12 Q26
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Correct answer: C
Question 54 — IGCSE 0653 Oct/Nov 2023 Paper 13 Q26
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Correct answer: C
Question 55 — IGCSE 0653 Oct/Nov 2023 Paper 11 Q27
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Correct answer: A
Question 56 — IGCSE 0653 Oct/Nov 2023 Paper 12 Q27
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Correct answer: C
Question 57 — IGCSE 0653 Oct/Nov 2023 Paper 13 Q27
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Correct answer: C
Question 58 — IGCSE 0653 Oct/Nov 2023 Paper 11 Q28
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Correct answer: D
Question 59 — IGCSE 0653 Oct/Nov 2023 Paper 12 Q28
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Correct answer: C
Question 60 — IGCSE 0653 Oct/Nov 2023 Paper 13 Q28
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Correct answer: C
Question 61 — IGCSE 0653 Oct/Nov 2023 Paper 11 Q29
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Correct answer: B
Question 62 — IGCSE 0653 Oct/Nov 2023 Paper 12 Q29
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Correct answer: A
Question 63 — IGCSE 0653 Oct/Nov 2023 Paper 13 Q29
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Correct answer: A
Question 64 — IGCSE 0653 Oct/Nov 2023 Paper 11 Q30
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Correct answer: A
Question 65 — IGCSE 0653 Oct/Nov 2023 Paper 12 Q30
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Correct answer: D
Question 66 — IGCSE 0653 Oct/Nov 2023 Paper 13 Q30
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Correct answer: D
Question 67 — IGCSE 0653 Oct/Nov 2023 Paper 12 Q31
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Correct answer: B
Question 68 — IGCSE 0653 Oct/Nov 2023 Paper 13 Q31
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Correct answer: B
Organic Chemistry — Extended MCQ36 · Paper 2
Question 1 — IGCSE 0653 Mar 2024 Paper 22 Q25
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Correct answer: A
Question 2 — IGCSE 0653 Mar 2024 Paper 22 Q26
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Correct answer: D
Question 3 — IGCSE 0653 Mar 2024 Paper 22 Q27
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Correct answer: D
Question 4 — IGCSE 0653 Mar 2024 Paper 22 Q28
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Correct answer: D
Question 5 — IGCSE 0653 May/Jun 2023 Paper 22 Q24
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Correct answer: C
Question 6 — IGCSE 0653 May/Jun 2023 Paper 22 Q25
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Correct answer: B
Question 7 — IGCSE 0653 May/Jun 2023 Paper 22 Q26
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Correct answer: C
Question 8 — IGCSE 0653 May/Jun 2023 Paper 23 Q26
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Correct answer: C
Question 9 — IGCSE 0653 May/Jun 2023 Paper 22 Q27
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Correct answer: A
Question 10 — IGCSE 0653 May/Jun 2023 Paper 23 Q27
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Correct answer: D
Question 11 — IGCSE 0653 May/Jun 2023 Paper 23 Q28
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Correct answer: C
Question 12 — IGCSE 0653 May/Jun 2023 Paper 23 Q29
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Correct answer: C
Question 13 — IGCSE 0653 May/Jun 2023 Paper 23 Q30
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Correct answer: C
Question 14 — IGCSE 0653 May/Jun 2024 Paper 22 Q22
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Correct answer: C
Question 15 — IGCSE 0653 May/Jun 2024 Paper 22 Q23
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Correct answer: D
Question 16 — IGCSE 0653 May/Jun 2024 Paper 22 Q24
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Correct answer: D
Question 17 — IGCSE 0653 May/Jun 2024 Paper 21 Q25
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Correct answer: D
Question 18 — IGCSE 0653 May/Jun 2024 Paper 22 Q25
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Correct answer: C
Question 19 — IGCSE 0653 May/Jun 2024 Paper 21 Q26
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Correct answer: C
Question 20 — IGCSE 0653 May/Jun 2024 Paper 22 Q26
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Correct answer: C
Question 21 — IGCSE 0653 May/Jun 2024 Paper 21 Q27
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Correct answer: A
Question 22 — IGCSE 0653 May/Jun 2024 Paper 22 Q27
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Correct answer: B
Question 23 — IGCSE 0653 May/Jun 2024 Paper 21 Q28
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Correct answer: C
Question 24 — IGCSE 0653 May/Jun 2025 Paper 21 Q20
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Correct answer: D
Question 25 — IGCSE 0653 May/Jun 2025 Paper 21 Q21
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Correct answer: C
Question 26 — IGCSE 0653 May/Jun 2025 Paper 22 Q21
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Correct answer: A
Question 27 — IGCSE 0653 May/Jun 2025 Paper 21 Q22
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Correct answer: A
Question 28 — IGCSE 0653 May/Jun 2025 Paper 22 Q22
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Correct answer: A
Question 29 — IGCSE 0653 May/Jun 2025 Paper 22 Q23
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Correct answer: D
Question 30 — IGCSE 0653 May/Jun 2025 Paper 22 Q24
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Correct answer: C
Question 31 — IGCSE 0653 May/Jun 2025 Paper 22 Q25
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Correct answer: D
Question 32 — IGCSE 0653 Oct/Nov 2023 Paper 22 Q24
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Correct answer: A
Question 33 — IGCSE 0653 Oct/Nov 2023 Paper 22 Q25
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Correct answer: B
Question 34 — IGCSE 0653 Oct/Nov 2023 Paper 22 Q26
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Correct answer: B
Question 35 — IGCSE 0653 Oct/Nov 2023 Paper 22 Q27
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Correct answer: C
Question 36 — IGCSE 0653 Oct/Nov 2023 Paper 22 Q28
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Correct answer: C
All Organic Chemistry questions in this collection
| Type | Level | Paper | Session | Q# | Marks | Answer / key |
|---|---|---|---|---|---|---|
| MCQ | Core | Paper 12 | Mar 2023 | Q21 | 1 mark | A |
| MCQ | Core | Paper 12 | Mar 2023 | Q22 | 1 mark | D |
| MCQ | Core | Paper 12 | Mar 2023 | Q23 | 1 mark | C |
| MCQ | Core | Paper 12 | Mar 2023 | Q24 | 1 mark | D |
| MCQ | Core | Paper 12 | Mar 2023 | Q25 | 1 mark | A |
| MCQ | Core | Paper 12 | Mar 2023 | Q26 | 1 mark | B |
| MCQ | Core | Paper 12 | Mar 2023 | Q27 | 1 mark | A |
| MCQ | Core | Paper 12 | Mar 2023 | Q28 | 1 mark | D |
| MCQ | Core | Paper 12 | Mar 2023 | Q29 | 1 mark | D |
| MCQ | Core | Paper 12 | Mar 2023 | Q30 | 1 mark | A |
| MCQ | Core | Paper 12 | Mar 2025 | Q14 | 1 mark | D |
| MCQ | Core | Paper 12 | Mar 2025 | Q15 | 1 mark | B |
| MCQ | Core | Paper 12 | Mar 2025 | Q16 | 1 mark | C |
| MCQ | Core | Paper 12 | Mar 2025 | Q17 | 1 mark | B |
| MCQ | Core | Paper 12 | Mar 2025 | Q21 | 1 mark | D |
| MCQ | Core | Paper 12 | Mar 2025 | Q22 | 1 mark | A |
| MCQ | Core | Paper 12 | Mar 2025 | Q23 | 1 mark | B |
| MCQ | Core | Paper 12 | Mar 2025 | Q24 | 1 mark | A |
| MCQ | Core | Paper 12 | Mar 2025 | Q25 | 1 mark | B |
| MCQ | Core | Paper 11 | May/Jun 2023 | Q26 | 1 mark | C |
| MCQ | Core | Paper 11 | May/Jun 2023 | Q27 | 1 mark | A |
| MCQ | Core | Paper 11 | May/Jun 2023 | Q28 | 1 mark | B |
| MCQ | Core | Paper 11 | May/Jun 2023 | Q29 | 1 mark | D |
| MCQ | Core | Paper 12 | May/Jun 2024 | Q17 | 1 mark | B |
| MCQ | Core | Paper 12 | May/Jun 2024 | Q18 | 1 mark | D |
| MCQ | Core | Paper 12 | May/Jun 2024 | Q19 | 1 mark | D |
| MCQ | Core | Paper 12 | May/Jun 2024 | Q20 | 1 mark | A |
| MCQ | Core | Paper 11 | May/Jun 2024 | Q21 | 1 mark | D |
| MCQ | Core | Paper 12 | May/Jun 2024 | Q21 | 1 mark | C |
| MCQ | Core | Paper 11 | May/Jun 2024 | Q22 | 1 mark | D |
| MCQ | Core | Paper 11 | May/Jun 2024 | Q23 | 1 mark | C |
| MCQ | Core | Paper 11 | May/Jun 2024 | Q24 | 1 mark | C |
| MCQ | Core | Paper 11 | May/Jun 2024 | Q25 | 1 mark | A |
| MCQ | Core | Paper 12 | May/Jun 2024 | Q25 | 1 mark | C |
| MCQ | Core | Paper 11 | May/Jun 2024 | Q26 | 1 mark | C |
| MCQ | Core | Paper 12 | May/Jun 2024 | Q26 | 1 mark | B |
| MCQ | Core | Paper 11 | May/Jun 2024 | Q27 | 1 mark | B |
| MCQ | Core | Paper 12 | May/Jun 2024 | Q27 | 1 mark | C |
| MCQ | Core | Paper 11 | May/Jun 2024 | Q28 | 1 mark | D |
| MCQ | Core | Paper 12 | May/Jun 2024 | Q28 | 1 mark | D |
| MCQ | Core | Paper 12 | May/Jun 2024 | Q29 | 1 mark | B |
| MCQ | Core | Paper 11 | May/Jun 2025 | Q17 | 1 mark | B |
| MCQ | Core | Paper 11 | May/Jun 2025 | Q18 | 1 mark | A |
| MCQ | Core | Paper 11 | May/Jun 2025 | Q19 | 1 mark | D |
| MCQ | Core | Paper 12 | Oct/Nov 2023 | Q22 | 1 mark | C |
| MCQ | Core | Paper 13 | Oct/Nov 2023 | Q22 | 1 mark | C |
| MCQ | Core | Paper 12 | Oct/Nov 2023 | Q23 | 1 mark | C |
| MCQ | Core | Paper 13 | Oct/Nov 2023 | Q23 | 1 mark | C |
| MCQ | Core | Paper 12 | Oct/Nov 2023 | Q24 | 1 mark | A |
| MCQ | Core | Paper 13 | Oct/Nov 2023 | Q24 | 1 mark | A |
| MCQ | Core | Paper 12 | Oct/Nov 2023 | Q25 | 1 mark | A |
| MCQ | Core | Paper 13 | Oct/Nov 2023 | Q25 | 1 mark | A |
| MCQ | Core | Paper 12 | Oct/Nov 2023 | Q26 | 1 mark | C |
| MCQ | Core | Paper 13 | Oct/Nov 2023 | Q26 | 1 mark | C |
| MCQ | Core | Paper 11 | Oct/Nov 2023 | Q27 | 1 mark | A |
| MCQ | Core | Paper 12 | Oct/Nov 2023 | Q27 | 1 mark | C |
| MCQ | Core | Paper 13 | Oct/Nov 2023 | Q27 | 1 mark | C |
| MCQ | Core | Paper 11 | Oct/Nov 2023 | Q28 | 1 mark | D |
| MCQ | Core | Paper 12 | Oct/Nov 2023 | Q28 | 1 mark | C |
| MCQ | Core | Paper 13 | Oct/Nov 2023 | Q28 | 1 mark | C |
| MCQ | Core | Paper 11 | Oct/Nov 2023 | Q29 | 1 mark | B |
| MCQ | Core | Paper 12 | Oct/Nov 2023 | Q29 | 1 mark | A |
| MCQ | Core | Paper 13 | Oct/Nov 2023 | Q29 | 1 mark | A |
| MCQ | Core | Paper 11 | Oct/Nov 2023 | Q30 | 1 mark | A |
| MCQ | Core | Paper 12 | Oct/Nov 2023 | Q30 | 1 mark | D |
| MCQ | Core | Paper 13 | Oct/Nov 2023 | Q30 | 1 mark | D |
| MCQ | Core | Paper 12 | Oct/Nov 2023 | Q31 | 1 mark | B |
| MCQ | Core | Paper 13 | Oct/Nov 2023 | Q31 | 1 mark | B |
| MCQ | Extended | Paper 22 | Mar 2024 | Q25 | 1 mark | A |
| MCQ | Extended | Paper 22 | Mar 2024 | Q26 | 1 mark | D |
| MCQ | Extended | Paper 22 | Mar 2024 | Q27 | 1 mark | D |
| MCQ | Extended | Paper 22 | Mar 2024 | Q28 | 1 mark | D |
| MCQ | Extended | Paper 22 | May/Jun 2023 | Q24 | 1 mark | C |
| MCQ | Extended | Paper 22 | May/Jun 2023 | Q25 | 1 mark | B |
| MCQ | Extended | Paper 22 | May/Jun 2023 | Q26 | 1 mark | C |
| MCQ | Extended | Paper 23 | May/Jun 2023 | Q26 | 1 mark | C |
| MCQ | Extended | Paper 22 | May/Jun 2023 | Q27 | 1 mark | A |
| MCQ | Extended | Paper 23 | May/Jun 2023 | Q27 | 1 mark | D |
| MCQ | Extended | Paper 23 | May/Jun 2023 | Q28 | 1 mark | C |
| MCQ | Extended | Paper 23 | May/Jun 2023 | Q29 | 1 mark | C |
| MCQ | Extended | Paper 23 | May/Jun 2023 | Q30 | 1 mark | C |
| MCQ | Extended | Paper 22 | May/Jun 2024 | Q22 | 1 mark | C |
| MCQ | Extended | Paper 22 | May/Jun 2024 | Q23 | 1 mark | D |
| MCQ | Extended | Paper 22 | May/Jun 2024 | Q24 | 1 mark | D |
| MCQ | Extended | Paper 21 | May/Jun 2024 | Q25 | 1 mark | D |
| MCQ | Extended | Paper 22 | May/Jun 2024 | Q25 | 1 mark | C |
| MCQ | Extended | Paper 21 | May/Jun 2024 | Q26 | 1 mark | C |
| MCQ | Extended | Paper 22 | May/Jun 2024 | Q26 | 1 mark | C |
| MCQ | Extended | Paper 21 | May/Jun 2024 | Q27 | 1 mark | A |
| MCQ | Extended | Paper 22 | May/Jun 2024 | Q27 | 1 mark | B |
| MCQ | Extended | Paper 21 | May/Jun 2024 | Q28 | 1 mark | C |
| MCQ | Extended | Paper 21 | May/Jun 2025 | Q20 | 1 mark | D |
| MCQ | Extended | Paper 21 | May/Jun 2025 | Q21 | 1 mark | C |
| MCQ | Extended | Paper 22 | May/Jun 2025 | Q21 | 1 mark | A |
| MCQ | Extended | Paper 21 | May/Jun 2025 | Q22 | 1 mark | A |
| MCQ | Extended | Paper 22 | May/Jun 2025 | Q22 | 1 mark | A |
| MCQ | Extended | Paper 22 | May/Jun 2025 | Q23 | 1 mark | D |
| MCQ | Extended | Paper 22 | May/Jun 2025 | Q24 | 1 mark | C |
| MCQ | Extended | Paper 22 | May/Jun 2025 | Q25 | 1 mark | D |
| MCQ | Extended | Paper 22 | Oct/Nov 2023 | Q24 | 1 mark | A |
| MCQ | Extended | Paper 22 | Oct/Nov 2023 | Q25 | 1 mark | B |
| MCQ | Extended | Paper 22 | Oct/Nov 2023 | Q26 | 1 mark | B |
| MCQ | Extended | Paper 22 | Oct/Nov 2023 | Q27 | 1 mark | C |
| MCQ | Extended | Paper 22 | Oct/Nov 2023 | Q28 | 1 mark | C |
| Theory | Core | Paper 33 | May/Jun 2023 | Q2 | 8 marks | thermometer |
| Theory | Core | Paper 32 | May/Jun 2023 | Q8 | 8 marks | methane + oxygen carbon dioxide + water |
| Theory | Core | Paper 31 | May/Jun 2024 | Q5 | 10 marks | fractional distillation (circled) |
| Theory | Core | Paper 32 | Oct/Nov 2023 | Q5 | 6 marks | fractional distillation |
| Theory | Core | Paper 33 | Oct/Nov 2023 | Q5 | 6 marks | fractional distillation |
| Theory | Extended | Paper 42 | Mar 2023 | Q8 | 9 marks | alkane |
| Theory | Extended | Paper 42 | May/Jun 2023 | Q8 | 9 marks | decane and pentane |
| Theory | Extended | Paper 43 | May/Jun 2023 | Q8 | 9 marks | ethene and butene |
| Theory | Extended | Paper 41 | May/Jun 2024 | Q8 | 9 marks | cracking |
| Theory | Extended | Paper 41 | May/Jun 2025 | Q5 | 9 marks | red-brown |
| Theory | Extended | Paper 43 | May/Jun 2025 | Q5 | 9 marks | bromine |
| Theory | Extended | Paper 43 | Oct/Nov 2023 | Q8 | 8 marks | C H |