Organic chemistry — IGCSE Chemistry (0971) questions by topic
Organic chemistry questions cover fractional distillation of petroleum in order of boiling point, comparing ethanol production by fermentation against reacting ethene with steam, defining what a hydrocarbon is, and identifying structures such as a four-carbon ring from a set of displayed formulae. State and identify want short definitions or selections, while deduce, draw and explain test working out structures and reasoning about industrial processes.
31 questions drawn from 2025 papers make up this set, worth between 1 and 18 marks. Because structural questions are marked on exact bonding and formula detail, submitting an answer for instant marking checks whether a drawn or deduced structure, such as a ring compound against a straight chain, has actually matched the formula given rather than looking similar at a glance.
May–June 2025, Paper 11
A hydrogen-oxygen fuel cell uses 630 dm^3 of oxygen. The oxygen for the reaction is extracted from clean, dry air. What is the minimum volume of clean, dry air needed to provide…
Answer this question and get it marked →What is produced by the incomplete combustion of methane? A carbon monoxide B hydrogen C lead compounds D sulfur dioxide
Answer this question and get it marked →Which row identifies compounds in the same homologous series? chemical properties functional group A different different B different same C similar different D similar same
Answer this question and get it marked →The molecular formula of compound Z is C4H10. Which row identifies the substance that reacts with Z and describes the type of reaction that occurs? substance type of reaction A…
Answer this question and get it marked →Which list shows the fractions obtained from the fractional distillation of petroleum, in order of increasing boiling point? A bitumen → diesel oil → fuel oil → lubricating oil B…
Answer this question and get it marked →Three statements about cracking of larger alkane molecules are listed. 1 Cracking produces petrol for cars. 2 Cracking only produces short-chain alkenes. 3 Cracking produces…
Answer this question and get it marked →Some words used to describe organic compounds are listed. 1 hydrocarbon 2 monomer 3 saturated 4 unreactive Which words describe ethene? A 1 and 2 B 1 and 3 C 2 and 4 D 3 and 4
Answer this question and get it marked →May–June 2025, Paper 12
The diagrams show the structures of four molecules. The four displayed structural formulae are: molecule 1 is cyclobutane (a four-carbon ring, each carbon bonded to two hydrogens,…
Answer this question and get it marked →Which equation represents the overall reaction that produces electricity in a hydrogen-oxygen fuel cell? A H2 + O2 - H2O2 B 2H2O - 2H2 + O2 C 2H2 + O2 - 2H2O D 2H2O2 - 2H2O + O2
Answer this question and get it marked →The formulae for three organic compounds are listed. 1 C2H4 2 C4H8 3 C4H10 Which compounds belong to the same homologous series? A 1, 2 and 3 B 1 and 2 only C 1 and 3 only D 2 and…
Answer this question and get it marked →Which fuel could be gasoline? A flow chart is shown. The first question is 'Is it obtained from petroleum?'. If yes, it leads to a second question 'Is it used as fuel for cars?'…
Answer this question and get it marked →Three hydrocarbons are separately mixed with aqueous bromine. The three hydrocarbons, shown as displayed formulae, are: methane (CH4, all single bonds), ethane (C2H6, all single…
Answer this question and get it marked →Which compound is formed when ethene reacts with steam? A ethane B ethanoic acid C ethanol D poly(ethene)
Answer this question and get it marked →Which statements about ethanoic acid are correct? 1 Its aqueous solution has a pH value of 10. 2 It reacts with metal carbonates to produce carbon dioxide gas. 3 It reacts with…
Answer this question and get it marked →Which statement explains why plastic bags made from poly(ethene) accumulate in oceans? A Poly(ethene) is a saturated molecule. B Poly(ethene) is made from hydrocarbon monomers. C…
Answer this question and get it marked →May–June 2025, Paper 21
The equation represents the reaction between ethanoic acid and ethanol. CH3COOH + CH3CH2OH <= CH3COOCH2CH3 + H2O Which type of reaction does this show? A addition B neutralisation…
Answer this question and get it marked →Ethanol is warmed with acidified aqueous potassium manganate(VII). Which row describes the type of reaction of the ethanol and the colour change observed in the reaction mixture?…
Answer this question and get it marked →The structural formula of methyl ethanoate is CH3COOCH3. Which compounds are structural isomers of methyl ethanoate? 1 HCOOCH2CH3 2 CH3CH2COOH 3 HOCH2CH2CH2OH A 1, 2 and 3 B 1 and…
Answer this question and get it marked →What is the total number of covalent bonds in one molecule of propane? A 8 B 9 C 10 D 11
Answer this question and get it marked →Industrially, ethanol is produced by fermentation or by the reaction of ethene with steam. Which row is correct? The options compare fermentation with ethene + steam: A…
Answer this question and get it marked →Some properties of an organic compound, J, are listed. - It is a liquid at room temperature. - It is soluble in water. - A solution of J reacts with calcium carbonate to form…
Answer this question and get it marked →The structures of two monomers that are used to make a condensation polymer are shown. The first monomer is a dicarboxylic acid: HOOC-COOH (two C=O carbons each bonded to an -OH…
Answer this question and get it marked →May–June 2025, Paper 22
What is the structural formula of butan-2-ol? A CH3CH2CH2OH B CH3CH(OH)CH3 C CH3CH2CH2CH2OH D CH3CH2CH(OH)CH3
Answer this question and get it marked →Methanol reacts with ethanoic acid to form an ester. What is the displayed formula for this ester? A, B, C and D are displayed formulae of esters showing all bonds. A an ester…
Answer this question and get it marked →Petroleum can be separated into useful fractions by fractional distillation. Which row shows a correct use of the named fraction? fraction use --- --- --- A bitumen lubricant B…
Answer this question and get it marked →Ethane reacts with chlorine in the presence of ultraviolet light. Which products are formed? A ClCH2CH2Cl and H2 B 2CH3Cl and H2 C C2H5Cl and HCl D CH2=CH2 and 2HCl
Answer this question and get it marked →Ethanol can be made by the fermentation of aqueous glucose and by the catalytic addition of steam to ethene. What are two advantages of making ethanol by the catalytic addition of…
Answer this question and get it marked →The structure of a polymer repeat unit is shown. The repeat unit contains an amide (N-C linkage with adjacent C=O groups), indicating a condensation polymer (polyamide/nylon type)…
Answer this question and get it marked →May–June 2025, Paper 31
This question is about organic chemistry. Name the process that separates petroleum into its useful components.
Answer this question and get it marked →May–June 2025, Paper 32
This question is about organic chemistry. State the meaning of the term hydrocarbon.
Answer this question and get it marked →May–June 2025, Paper 42
Ethene, C2H4, is the first member of a family of similar compounds which contains the alkene functional group. State the term for a family of similar compounds which contain the…
Answer this question and get it marked →Other IGCSE Chemistry topics
- The Periodic Table (29)
- Metals (23)
- Experimental techniques and chemical analysis (19)
- Chemical reactions (14)
- Acids, bases and salts (14)
- Chemical bonding (11)
- Stoichiometry (11)
- Chemistry of the environment (10)
- States of matter (9)
- Electrochemistry (9)
- Atoms, elements and compounds (8)
- Chemical energetics (8)