Organic chemistry — IGCSE Sciences - Co-Ordinated (0654) questions by topic
16 organic chemistry questions from 2023 and 2024 span 7 to 12 marks, testing whether you can pick an unsaturated hydrocarbon from displayed formulae, name methane's fossil fuel source, and state what the term hydrocarbon actually means.
State, describe and identify head the command words, often paired with draw where a displayed formula must be produced rather than just recognised. Because naming the correct fossil fuel or distinguishing an alcohol from a hydrocarbon hinges on precise terminology, submit your structure and definition answers for instant marking to catch any confused compound name before it recurs across several linked questions.
What examiners look for
- Examiners repeatedly report carbon monoxide, methane and ethane offered as incorrect answers where a different named fossil fuel or compound was required.
- A recurring criticism is that few candidates knew the aqueous bromine test, and some struggled to describe the colour change it produces.
- Reports note that petrol, diesel and oil were not accepted as answers where natural gas specifically was the expected response.
- Few candidates could describe the actual test used to distinguish a saturated hydrocarbon from an unsaturated one.
- Where diagrams were given, many candidates did correctly identify which compound represented an alcohol.
May–June 2024, Paper 31
Petroleum is separated into different fractions. Table 8.1 shows the percentage composition of a 500 kg sample of petroleum. Identify fraction X.
Answer this question and get it marked →May–June 2024, Paper 32
Ethanol has the formula C2H5OH. Complete Fig. 5.1 to show the structure of an ethanol molecule. (Fig. 5.1 shows two C atoms.)
Answer this question and get it marked →May–June 2024, Paper 33
Ethanol has the formula C2H5OH. Complete Fig. 5.1 to show the structure of an ethanol molecule. (Fig. 5.1 shows two C atoms.)
Answer this question and get it marked →May–June 2024, Paper 42
Fig. 8.1 shows the structures of three carbon compounds: ethene (C2H4, with a C=C double bond), ethanoic acid and ethanol. Ethene is an unsaturated hydrocarbon. Explain how the…
Answer this question and get it marked →May–June 2024, Paper 43
Petroleum is a mixture of hydrocarbons. State what is meant by a hydrocarbon.
Answer this question and get it marked →October–November 2024, Paper 31
Fig. 11.1 shows the molecular structure of ethene (H2C=CH2, with a C=C double bond and each carbon bonded to two hydrogen atoms). State the total number of atoms in a molecule of…
Answer this question and get it marked →October–November 2024, Paper 42
Fig. 5.1 shows the structures of four carbon compounds: A (ethane, H3C-CH3); B (a poly(ethene) repeat unit with brackets); C (ethanol, CH3-CH2-OH); D (ethene, H2C=CH2). State…
Answer this question and get it marked →October–November 2024, Paper 43
Fig. 2.1 shows the displayed formulae of some carbon compounds: A (ethene, H2C=CH2); B (ethane, H3C-CH3); C (propane, H3C-CH2-CH3); D (ethanol, H3C-CH2-OH). State which compound…
Answer this question and get it marked →May–June 2023, Paper 32
Fig. 8.1 shows the separation of petroleum into useful fractions; only two fractions are shown (refinery gas at 50 °C, diesel oil at 400 °C). Petroleum is a fossil fuel. State the…
Answer this question and get it marked →May–June 2023, Paper 33
Fig. 8.1 shows the separation of petroleum into useful fractions; only two fractions are shown (refinery gas at 50 °C, diesel oil at 400 °C). Petroleum is a fossil fuel. State the…
Answer this question and get it marked →May–June 2023, Paper 41
Look at the structures of the carbon compounds A–E shown in Fig. 11.1 (A is ethene C2H4; B is ethanol; C is ethane; D and E other structures). State which compound is made by the…
Answer this question and get it marked →May–June 2023, Paper 42
Alkanes are saturated hydrocarbons. State what is meant by the term saturated hydrocarbon.
Answer this question and get it marked →May–June 2023, Paper 43
Petroleum is separated into different fractions. Fig. 8.1 shows the percentage composition: gasoline 46%, diesel oil 26%, other products 11%, jet fuel 9%, heavy fuel oil 4%,…
Answer this question and get it marked →October–November 2023, Paper 31
State the compound from Table 5.1 that is an unsaturated hydrocarbon.
Answer this question and get it marked →October–November 2023, Paper 32
Methane, CH4, is the main constituent of a fossil fuel. State the name of this fossil fuel.
Answer this question and get it marked →October–November 2023, Paper 41
Crude oil contains hydrocarbon molecules. State what is meant by a hydrocarbon.
Answer this question and get it marked →Other IGCSE Sciences - Co-Ordinated topics
- Practical skills (146)
- Motion, forces and energy (41)
- Electricity and magnetism (15)
- Waves (14)
- Reproduction (13)
- Nuclear physics (13)
- Coordination and response (12)
- Organisms and their environment (12)
- Metals (11)
- Atoms, elements and compounds (10)
- Stoichiometry (9)
- Thermal physics (9)