O-Level Pure Chemistry — Theory Papers (P1 & P2)

Singapore-Cambridge GCE O-Level Pure Chemistry · Paper 1 (MCQ) + Paper 2 (Structured) · codes 5067 / 5073 / 6092 · 2009–2026

General

2025

2026

35 papers tagged (17 × P1, 18 × P2) · 1547 questions/sub-parts · 154/154 syllabus learning outcomes ever tested · 9 papers on the 2023 syllabus. Every question is tagged to the 2023 syllabus learning outcomes; pre-2023 papers are mapped onto the same codes so trends are comparable. Content removed in 2023 is kept visible in the history but excluded from all predictions. Predictions weight recent papers more heavily (half-life 6 years, 2023-syllabus papers ×1.6). 2 specimen paper(s) are tagged: they count towards syllabus coverage and appear as reference columns in the heat map, but are left out of the year-by-year trend and the forecast since nobody sat them.

Year	Paper	Syllabus	What was asked — question by question	Dead content
2026Oct/Nov 2026	P2	2023 syl6092	Q1Ch 128mname two pollutant gases that cause acid rain (SO2 and NO2) Q2Ch 107meffect of lowering glucose concentration on rate, using frequency of collisions between pa Q3Ch 26mhow the structure of a 79Br atom differs from an 81Br atom (two fewer neutrons) Q4Ch 45mtotal percentage by mass of the metals (Pb and Cr) in lead(II) chromate PbCrO4 Q5Ch 4, 116mempirical formula of a hydrocarbon containing 81.8% carbon by mass (C3H8) Q6Ch 9, 118mcomplete tables of bond types and numbers in ethene + water and in ethanol (C-C, C-H, C-O, Q7Ch 4, 710melectrolysis of dilute CuSO4(aq) with inert electrodes: appearance and pH once the copper- Q8Ch 3, 4, 7, 812mmass of CoO2 in a 30.0 g lithium-ion battery that is 15.0% cobalt by mass Q9Ch 3, 5, 118mcomplete the dot-and-cross diagram of the PAA monomer C2H3COOH (C=C, C=O, O-H, outer elect Q10 optionalCh 310mpredict and explain state and conductivity of SiO2 (still solid) and NaCl (molten) at 1000 Q11 optionalCh 3, 810mexplain solid state, mp 420 C, conductivity and malleability of metal Y from a metallic la	—
2025October/November 2025	P1	2023 syl6092	Q1 C1Q2 C1Q3 C1Q4 C1Q5 C1Q6 C2Q7 C2Q8 C3Q9 C3Q10 C3Q11 C4Q12 C4Q13 C4Q14 C4Q15 C4Q16 C5Q17 C5Q18 C5Q19 C5Q20 C5Q21 C6Q22 C7Q23 C7Q24 C7Q25 C7Q26 C7Q27 C8Q28 C8Q29 C8Q30 C8Q31 C9Q32 C10Q33 C10Q34 C11Q35 C11Q36 C11Q37 C11Q38 C11Q39 C12Q40 C12	—
2025Oct/Nov 2025	P2	2023 syl6092	Q1Ch 39mcompare electrical conductivity of a metal and an ionic compound using structure Q2Ch 2, 3, 47mdot-and-cross diagram for NO (outer electrons only), double bond given Q3Ch 4, 119mmolecular and empirical formulae of the diol and dicarboxylic acid from depolymerising a p Q4Ch 1111methanol + methanoic acid: draw and name the ester (ethyl methanoate) Q5Ch 4, 5, 7, 88mmetal + aqueous cation temperature-change table: explain the two zero temperature changes Q6Ch 2, 3, 46mexplain in terms of atomic structure why Cl-35 and Cl-37 are isotopes Q7Ch 1, 2, 4, 7, 9, 1212mdraw energy profiles for endothermic SMR and exothermic WGS with Ea and dH labelled Q8Ch 4, 5, 7, 8, 98mpredict pH when SO2 dissolves in water and explain (acidic oxide) Q9 optionalCh 4, 510mcalculate concentration of Na2CO3(aq) from 39.50 cm3 of 0.10 mol/dm3 HCl titrated with 25. Q10 optionalCh 4, 510mdeduce limiting reactant for 1.0 g CaCO3 with 25.0 cm3 of 0.5 mol/dm3 HCl, with balanced e	—
2024October/November 2024	P1	2023 syl6092	Q1 C1Q2 C1Q3 C1Q4 C1Q5 C1Q6 C2Q7 C2Q8 C2Q9 C3Q10 C3Q11 C3Q12 C3Q13 C4Q14 C4Q15 C4Q16 C4Q17 C5Q18 C5Q19 C6Q20 C6Q21 C7Q22 C7Q23 C7Q24 C7Q25 C7Q26 C8Q27 C8Q28 C8Q29 C4Q30 C9Q31 C9Q32 C10Q33 C11Q34 C11Q35 C11Q36 C11Q37 C11Q38 C11Q39 C11Q40 C12	—
2024Oct/Nov 2024	P2	2023 syl6092	Q1Ch 4, 118mvolume of air (21% O2) at r.t.p. for complete combustion of 100 cm3 of propene Q2Ch 3, 410mclassify iron, iron(III) oxide/haematite and steel to explain element vs compound vs mixtu Q3Ch 4, 86mcomplete metal/metal-nitrate displacement grid for Ag, Pb, Zn, Fe, Mg Q4Ch 57muse % yield vs pressure/temperature graph to justify Haber conditions of 450 C and 200 atm Q5Ch 3, 4, 88mdot-and-cross diagram of the sulfate(VI) ion showing all outer-shell electrons (expanded o Q6Ch 3, 4, 511mcompare bonding in the elements carbon (giant covalent) and lead (metallic), referring to Q7Ch 4, 7, 10, 1112mmaximum mass of SO2 removed by 1000 kg of 98% pure limestone in flue gas desulfurisation Q8Ch 78melectrolysis of aqueous copper(II) sulfate with inert electrodes: changes in sulfate moles Q9 optionalCh 4, 5, 9, 1110menthalpy change on neutralising 25.0 cm3 of 0.05 mol/dm3 sulfuric acid given dH = -57 kJ/m Q10 optionalCh 4, 1010mpredict and explain time to collect 10 cm3 H2 from magnesium with nitric, sulfuric and eth	—
2024Specimen Paper (for examination from 2024)	SP P1SPECIMEN — not a sitting	2023 syl6092	Q1 C1Q2 C1Q3 C1Q4 C2Q5 C2Q6 C3Q7 C3Q8 C3Q9 C3Q10 C3Q11 C3Q12 C4Q13 C4Q14 C4Q15 C4Q16 C4Q17 C5Q18 C5Q19 C5Q20 C6Q21 C7Q22 C7Q23 C7Q24 C7Q25 C8Q26 C8Q27 C8Q28 C8Q29 C9Q30 C9Q31 C10Q32 C10Q33 C11Q34 C11Q35 C11Q36 C11Q37 C11Q38 C11Q39 C11Q40 C12	—
2024Specimen Paper (for examination from 2024)	SP P2SPECIMEN — not a sitting	2023 syl6092	Q1Ch 3, 4, 8, 127mselect element with five outer-shell electrons from a Periodic Table extract Q2Ch 3, 7, 810mbrush electroplating of zinc on iron: ionic half-equation with state symbols at cathode Q3Ch 4, 77mshow empirical formula of Martian rock compound Z is K2FeO4 from percentage by mass data Q4Ch 2, 5, 811mexplain why D2O percentage is lower in vapour first emerging from a heated tube (diffusion Q5Ch 2, 8, 117mtwo similarities between hydrogen and Group 1 elements Q6Ch 118mexplain how liquid fraction C is produced from crude oil by fractional distillation Q7Ch 7, 128mhow CO and NO form in a car engine and one health problem caused by each Q8Ch 1, 4, 812mdeduce which Group 1 elements are present/absent in a mixture from its emission spectrum Q9 optionalCh 4, 9, 1110mshow ethanol releases less energy per kg than propane using enthalpy of combustion data Q10 optionalCh 4, 1110mmaximum mass of ethanol from fermentation of 36 tonnes of glucose	—
2023Oct/Nov 2023	P1	2023 syl6092	Q1 C1Q2 C1Q3 C1Q4 C6Q5 C7Q6 C6Q7 C2Q8 C2Q9 C2Q10 C3Q11 C3Q12 C3Q13 C3Q14 C4Q15 C4Q16 C4Q17 C7Q18 C4Q19 C7Q20 C7Q21 C9Q22 C9Q23 C10Q24 C7Q25 C5Q26 C5Q27 C6Q28 C8Q29 C8Q30 C8Q31 C3Q32 C8Q33 C8Q34 C11Q35 C11Q36 C11Q37 C4Q38 C11Q39 C4Q40 C12	—
2023October/November 2023	P2	2023 syl6092	QA1Ch 2, 89mcomplete table of group/period, electronic configuration, neutrons and ion symbol for ions QA2Ch 79melectrolysis of aqueous silver nitrate with platinum electrodes: identify silver at cathod QA3Ch 4, 5, 7, 89mbalance the equation for roasting chalcopyrite 4CuFeS2 + O2 to copper, iron(III) oxide and QA4Ch 3, 4, 5, 810mtrend in metal:oxygen atom ratio down Group I from Li2O to Na2O2 to KO2 QA5Ch 9, 127mwhy atmospheric CO2 stayed stable for millions of years, referring to photosynthesis and d QA6Ch 116mone similarity and one difference between the monomers of a polyester repeat unit and thos QB7Ch 4, 9, 11, 1212mestimate the energy density of petrol in kJ/L from the enthalpy change of combustion of oc QB8Ch 7, 108mwhy gas volumes after 30s differ for excess zinc with 1.0 mol/dm3 H2SO4 vs HCl at 20C and QB9 eitherCh 4, 6, 810mreagents and procedures to test for calcium ions and nitrate ions in calcium nitrate solut QB9 orCh 4, 6, 810mtwo reagents (NaOH(aq) and aqueous ammonia) to distinguish aqueous lead, zinc and copper i	—
2022Oct/Nov 2022	P1	old syl6092	Q1 C1Q2 C1Q3 C6Q4 C2Q5 C3Q6 C3Q7 C3Q8 C4Q9 C4Q10 C4Q11 C4Q12 C4Q13 C7Q14 C7Q15 C9Q16 C9Q17 C10Q18 C10Q19 C7Q20 C5Q21 C5Q22 C5Q23 C5Q24 C5Q25 C4Q26 C8Q27 C8Q28 C8Q29 C8Q30 C8Q31 C2Q32 C11Q33 C11Q34 C11Q35 C11Q36 C11Q37 C11Q38 C11Q39 C12Q40 C11	3 marks R-BLASTFURNACE, R-FRACTIONUSES, R-RECYCLEMETAL
2022Oct/Nov 2022	P2	old syl6092	QA1Ch 3, 4, 86midentify Group V element from dot-and-cross diagrams of period 1-2 molecules QA2Ch 27mpredict/explain movement of Cu2+ vs V2+ ions in water at 20 vs 30 degrees C (mass and temp QA3Ch 4, 1110mempirical formula from 40.0% C, 6.7% H by mass QA4Ch 7, 8, 10, 129mcolour and state of chlorine, bromine, iodine at rtp QA5Ch 4, 7, 98mcomplete energy profile diagram for H2 + O2: combustion vs fuel cell pathway, Ea(1), Ea(2) QA6Ch 1, 4, 5, 7, 1210mevaluate whether ammonium sulfate recycling processes follow green chemistry principles (e QB7Ch 4, 1112mrange of mass of single LDPE molecule from 4000-40000 carbon atoms (CH2 units) QB8Ch 3, 88mexplain melting point and conductivity differences of lithium (metallic), graphite (giant QB9 eitherCh 710melectrolysis of dilute NaOH and dilute NaCl: explain 2:1 gas volume ratio and give half-eq QB9 orCh 710mzinc rod in CuSO4 (displacement) vs electrolysis of CuSO4 with carbon electrodes: observat	1 marks R-H2SO4USES
2021Oct/Nov 2021	P1	old syl6092	Q1 C1Q2 C2Q3 C6Q4 C2Q5 C2Q6 C3Q7 C3Q8 C3Q9 C4Q10 C4Q11 C4Q12 C4Q13 C7Q14 C9Q15 C10Q16 C7Q17 C5Q18 C5Q19 C9Q20 C6Q21 C8Q22 C8Q23 C8Q24 C8Q25 C3Q26 C8Q27 C8Q28 C8Q29 C12Q30 C12Q31 C7Q32 C11Q33 C11Q34 C11Q35 C11Q36 C11Q37 C11Q38 C11Q39 C11Q40 C11	1 marks R-FRACTIONUSES
2021Oct/Nov 2021	P2	old syl6092	QA1Ch 3, 5, 6, 88mtrue/false statements on group and period trends (noble gases, Period 2 melting points, Gr QA2Ch 4, 9, 1111mdescribe how fractional distillation of crude oil separates propane from octane QA3Ch 78mcomplete table of electrode products for electrolysis of dilute/concentrated NaCl(aq) and QA4Ch 4, 811mcalculate maximum mass of iron from 14000 tonnes of iron(III) oxide QA5Ch 3, 4, 1212mdot-and-cross diagram for urea (NH2)2CO in Diesel Exhaust Fluid QB6Ch 5, 1112mstate and explain factors affecting pH of an acid (concentration, strength, H+ per molecul QB7Ch 118mone similarity and two differences between condensation polymerisation of C and addition p QB8 eitherCh 3, 4, 810muse bonding and structure to explain mp/bp, density and conductivity differences of CO, Si QB8 orCh 4, 1010mcollision theory explanation of effect of iodide concentration, temperature and Cu2+ catal	6 marks R-BLASTFURNACE, R-STEELS
2020Oct/Nov 2020	P1	old syl6092	Q1 C1Q2 C1Q3 C6Q4 C1Q5 C2Q6 C2Q7 C2Q8 C3Q9 C4Q10 C4Q11 C4Q12 C7Q13 C7Q14 C9Q15 C9Q16 C10Q17 C10Q18 C7Q19 C5Q20 C5Q21 C5Q22 C5Q23 C8Q24 C8Q25 C8Q26 C8Q27 C7Q28 C8Q29 C12Q30 C12Q31 C1Q32 C3Q33 C5Q34 C11Q35 C11Q36 C11Q37 C11Q38 C11Q39 C11Q40 C11	3 marks R-BLASTFURNACE, R-NH3DISPLACE, R-STEELS
2020Oct/Nov 2020	P2	old syl6092	QA1Ch 3, 5, 7, 8, 118mtrue/false grid on uses of crude-oil fractions (naphtha, paraffin, bitumen, gasoline) QA2Ch 10, 126muse energy and collision ideas to explain why N2 + O2 react in a car engine but not in the QA3Ch 38mcomplete labels on structure diagrams of a metal (positive ions + electrons) and an ionic QA4Ch 5, 7, 119mdescribe electroplating set-up (electrodes, electrolyte) to coat an iron food can with tin QA5Ch 3, 510mdot-and-cross diagrams for MgO (ionic) and O2 (covalent), outer electrons only QA6Ch 4, 7, 89mevaluate two students' claims about mass of Group I hydride formed per gram of hydrogen QB7Ch 1, 4, 912mcompare freezing-point results for NaCl vs CaCl2 de-icer solutions (similarities and diffe QB8Ch 118mdeduce and draw structural formulae of C4H8O2 isomers (butanoic acid, methylpropanoic acid QB9 eitherCh 3, 4, 1110mcalculate mass of ethanol from 1000 dm3 ethene at rtp with 5% yield (ethene + steam proces QB9 orCh 4, 510mcalculate mass of H2SO4 needed to react with 1000 dm3 ammonia at rtp (2NH3 + H2SO4)	5 marks R-ETHANOLUSES, R-FRACTIONUSES, R-HABERCOND, R-STEELS
2018Oct/Nov 2018	P1	old syl6092	Q1 C2Q2 C1Q3 C6Q4 C1Q5 C2Q6 C3Q7 C3Q8 C3Q9 C3Q10 C12Q11 C4Q12 C4Q13 C7Q14 C7Q15 C7Q16 C9Q17 C9Q18 C10Q19 C10Q20 C7Q21 C7Q22 C5Q23 C5Q24 C5Q25 C8Q26 C8Q27 C8Q28 C3Q29 C8Q30 C8Q31 C8Q32 C8Q33 C4Q34 C9Q35 C11Q36 C11Q37 C11Q38 C11Q39 C11Q40 C11	1 marks R-LATTICE
2018Oct/Nov 2018	P2	old syl6092	QA1Ch 3, 5, 8, 127mtrue/false statements about sulfur dioxide: amphoteric?, erodes buildings, from volcanoes, QA2Ch 73mcomplete electrolysis table: conc CuCl2(aq)/carbon, dilute CuSO4(aq)/copper, molten NaCl/p QA3Ch 54mcomplete salt preparation table: CuCl2 from excess base + HCl, KNO3 by titration, PbSO4 by QA4Ch 3, 73mdescribe how metals (mobile electrons) and ionic solutions (mobile ions) conduct electrici QA5Ch 2, 4, 8, 129mexplain why using finite helium for party balloons should be discouraged (needed for MRI, QA6Ch 3, 4, 5, 9, 10, 1212mHaber process stages: why exothermic stage 2 at 450C needs less energy than endothermic st QA7Ch 4, 7, 812midentify what is reduced and oxidised when H2 reduces Ag2O; explain reasoning QB8Ch 1, 4, 612munfamiliar context: deduce which Group I elements are/are not in a mixture from emission s QB9Ch 4, 10, 118mtitration of used cooking oil with KOH(aq): calculate mass of KOH needed per kg of oil QB10 eitherCh 3, 810mexplain with equations why coke is essential to making iron from haematite in the blast fu QB10 orCh 1110mdescribe and explain how fractional distillation separates crude oil into fractions by boi	7 marks R-BLASTFURNACE, R-RECYCLEMETAL, R-STEELS
2017Oct/Nov 2017	P1	old syl5073	Q1 C1Q2 C6Q3 C2Q4 C2Q5 C8Q6 C3Q7 C3Q8 C3Q9 C4Q10 C4Q11 C7Q12 C7Q13 C7Q14 C9Q15 C11Q16 C10Q17 C7Q18 C7Q19 C5Q20 C5Q21 C5Q22 C5Q23 C8Q24 C8Q25 C8Q26 C6Q27 C8Q28 C3Q29 C5Q30 C8Q31 C8Q32 C4Q33 C12Q34 C10Q35 C11Q36 C11Q37 C11Q38 C11Q39 C11Q40 C11	1 marks R-BLASTFURNACE
2017Oct/Nov 2017	P2	old syl5073	QA1Ch 5, 7, 88mgive three characteristic properties of transition elements QA2Ch 4, 6, 7, 86mfill in state symbols for silver nitrate + potassium halide precipitation equation QA3Ch 126mwrite equations for photosynthesis and respiration QA4Ch 1111mexplain why cracking helps oil industry meet demand for crude oil fractions QA5Ch 4, 8, 99mcomplete energy profile diagram for exothermic Cr + CoSO4 displacement with dH and Ea labe QA6Ch 3, 4, 9, 10, 1210mdot-and-cross diagram for Freon-11 (CFCl3) QB7Ch 412mcompare Dalton's symbol formulae for water, HCl and NO with modern formulae QB8Ch 4, 78mcalculate molar volume of octane from density and enthalpy change per kg for octane and hy QB9 eitherCh 4, 1010mpredict rate and gas volume for 0.5 mol/dm3 ethanoic (weak) vs sulfuric (diprotic) acid wi QB9 orCh 3, 410mcompare bonding and structure of poly(propene), silicon dioxide and propanol	1 marks R-HABERCOND
2016Oct/Nov 2016	P1	old syl5073	Q1 C6Q2 C6Q3 C2Q4 C2Q5 C3Q6 C3Q7 C3Q8 C3Q9 C4Q10 C7Q11 C7Q12 C9Q13 C10Q14 C1Q15 C7Q16 C7Q17 C5Q18 C5Q19 C5Q20 C8Q21 C6Q22 C8Q23 C8Q24 C8Q25 C8Q26 C8Q27 C8Q28 C8Q29 C3Q30 C11Q31 C12Q32 C11Q33 C11Q34 C11Q35 C11Q36 C11Q37 C11Q38 C11Q39 C11Q40 C4	2 marks R-FRACTIONUSES, R-STEELS
2016Oct/Nov 2016	P2	old syl5073	QA1Ch 86mclassify periodic trends (electron shells, valency electrons, proton number, metallic-to-n QA2Ch 3, 7, 87muse oxidation states of Fe in Fe2O3/Fe cycle to identify extraction as reduction and rusti QA3Ch 2, 3, 5, 1211mdot-and-cross diagrams of covalent bonding in CO2 and O2 (outer shells only) QA4Ch 4, 510mcomplete table of fertiliser salts: name acid and other compound used to make K2SO4, K3PO4 QA5Ch 5, 116muse solubility rules to pick which salts (AgCl, BaSO4, PbSO4 vs KNO3, Na2CO3) can be made QA6Ch 4, 1110mdefine isomer; decide which of ethanol, methoxymethane, ethanal are isomers of each other QB7Ch 4, 1112mnylon comprehension: name nylon X (nylon 4,6) and nylon Y (nylon 11) from repeating-unit s QB8Ch 5, 108mexplain 1:3 N2:H2 volume ratio in Haber process using the balanced equation QB9 eitherCh 6, 710mobservations when zinc powder, acidified AgNO3, acidified Ba(NO3)2 and NaOH are added to C QB9 orCh 7, 810mcompare metal displacement (Fe/Cu2+) and halogen displacement (Cl2/Br-) as redox electron-	3 marks R-ESTERUSES, R-FRACTIONUSES, R-H2SO4USES
2015Oct/Nov 2015	P1	old syl5073	Q1 C1Q2 C1Q3 C5Q4 C3Q5 C3Q6 C9Q7 C3Q8 C3Q9 C3Q10 C3Q11 C3Q12 C3Q13 C4Q14 C7Q15 C4Q16 C4Q17 C7Q18 C8Q19 C9Q20 C5Q21 C7Q22 C8Q23 C5Q24 C6Q25 C5Q26 C8Q27 C8Q28 C8Q29 C3Q30 C4Q31 C8Q32 C1Q33 C11Q34 C9Q35 C11Q36 C11Q37 C4Q38 C11Q39 C11Q40 C11	2 marks R-BLASTFURNACE, R-FRACTIONUSES
2015Oct/Nov 2015	P2	old syl5073	QA1Ch 7, 86mexplain why no Group 0 (noble gas) elements appear in a table of common oxidation states QA2Ch 86mpredict minimum temperature for reduction of iron oxide by carbon with reasoning QA3Ch 5, 118mcomplete table of manufacture routes: cracking to ethene, polymerisation to poly(ethene), QA4Ch 3, 8, 128mexplain why extraction of aluminium from bauxite uses far more energy than recycling cans QA5Ch 711mionic equations at cathode and anode for electrolysis of dilute NaCl(aq) QA6Ch 4, 511mshow by calculation that CaO has higher % mass of calcium than CaCO3 and Ca(OH)2 QB7Ch 1112meffect of isomerisation (branching) on flashpoint, using evidence from tables of straight QB8Ch 128meffect of lean-burn engine (more air, lower temperature) on CO and NO formation QB9 eitherCh 2, 910mcompare energy diagrams and temperature changes for dissolving LiCl (exothermic) vs NaCl ( QB9 orCh 4, 7, 810mfluorine displaces bromine from KBr(aq) turning paper brown; ionic equation	3 marks R-RECYCLEMETAL
2014Oct/Nov 2014	P1	old syl5073	Q1 C1Q2 C1Q3 C6Q4 C2Q5 C3Q6 C2Q7 C3Q8 C3Q9 C8Q10 C3Q11 C4Q12 C7Q13 C4Q14 C7Q15 C8Q16 C7Q17 C10Q18 C5Q19 C5Q20 C8Q21 C4Q22 C8Q23 C3Q24 C8Q25 C8Q26 C3Q27 C8Q28 C12Q29 C10Q30 C12Q31 C7Q32 C8Q33 C11Q34 C4Q35 C11Q36 C11Q37 C4Q38 C11Q39 C11Q40 C11	2 marks R-BLASTFURNACE, R-LATTICE
2014October/November 2014	P2	old syl5073	QA1Ch 4, 55mchoose Ca(OH)2 as solid added to soil to raise pH QA2Ch 3, 4, 7, 86mexplain from atom-arrangement diagram why stainless steel is harder than pure iron QA3Ch 4, 118mthree differences between addition and condensation polymerisation QA4Ch 9, 1112mbond breaking/forming explains why all combustion enthalpies are negative QA5Ch 710melectrode half-equations with state symbols for electrolysis of CuSO4(aq), carbon electrod QA6Ch 9, 119menergy profile diagram for endothermic cracking showing catalysed and uncatalysed activati QB7Ch 4, 512mdeduce H2SO4 concentration from NaOH volume at titration graph step QB8Ch 38msimilarities and differences in bonding and structure of diamond and graphite QB9 eitherCh 3, 4, 5, 7, 810mmass of bromine needed to make 54.2 g of PBr3 QB9 orCh 2, 3, 810mcomplete table of electron shells in Group I +1 ions and Group VII -1 ions	—
2013Oct/Nov 2013	P1	old syl5067	Q1 C1Q2 C2Q3 C6Q4 C1Q5 C2Q6 C3Q7 C3Q8 C3Q9 C4Q10 C4Q11 C5Q12 C7Q13 C9Q14 C8Q15 C7Q16 C11Q17 C4Q18 C5Q19 C5Q20 C8Q21 C8Q22 C8Q23 C10Q24 C7Q25 C4Q26 C5Q27 C5Q28 C7Q29 C8Q30 C8Q31 C8Q32 C8Q33 C8Q34 C8Q35 C11Q36 C11Q37 C11Q38 C11Q39 C11Q40 C11	2 marks R-BLASTFURNACE, R-NH3DISPLACE
2013Oct/Nov 2013	P2	old syl5067	QA1Ch 3, 5, 7, 8, 127mcompare properties of high-carbon vs low-carbon steel QA2Ch 36mdot-and-cross diagram for carbon disulfide CS2 QA3Ch 1010mcollision theory explanation of concentration effect on thiosulfate reaction times QA4Ch 4, 5, 6, 7, 89mdeduce formula and name of product X (K2SO4) from the redox equation QA5Ch 7, 9, 128mwhy petrol-engine exhaust (CO, NOx) harms health more than fuel-cell product (water) QA6Ch 1, 4, 510mtitration of crushed aspirin tablet with 0.10 mol/dm3 NaOH to verify 300 mg label claim QB7Ch 4, 5, 7, 812mevaluate whether hydrolysis of Period 3 chlorides correlates with metallic character or bo QB8Ch 6, 7, 88melectrode equations for silver electroplating with carbon anode vs silver anode in AgNO3(a QB9 eitherCh 4, 1110mmole calculation: number of C=C double bonds per fat molecule (Mr 400, 100 g fat reacts wi QB9 orCh 4, 1210mreacting-mass calculation shows solid (1.07 g from 1.00 g Cu) contains unreacted copper	2 marks R-STEELS
2012Oct/Nov 2012	P1	old syl5067	Q1 C2Q2 C1Q3 C6Q4 C7Q5 C2Q6 C3Q7 C4Q8 C3Q9 C3Q10 C5Q11 C7Q12 C4Q13 C7Q14 C4Q15 C11Q16 C4Q17 C7Q18 C9Q19 C5Q20 C6Q21 C7Q22 C10Q23 C5Q24 C5Q25 C8Q26 C3Q27 C8Q28 C12Q29 C8Q30 C8Q31 C3Q32 C8Q33 C12Q34 C11Q35 C11Q36 C11Q37 C11Q38 C11Q39 C11Q40 C4	2 marks R-BLASTFURNACE, R-HABERCOND
2012October/November 2012	P2	old syl5067	QA1Ch 56mflow chart of dilute H2SO4 reactions: identify which unknown is Universal Indicator (red s QA2Ch 2, 84misotope table: pick two isotopes with same number of protons (C-12 and C-14) QA3Ch 7, 129mexplain formation of nitrogen oxides in an aircraft engine (N2 + O2 at high temperature) QA4Ch 118mname and structural formula of next member of ethanoyl chloride homologous series QA5Ch 4, 5, 911mcomplete energy profile diagram for endothermic change, labelling enthalpy change and acti QA6Ch 3, 812mexplain via bonding why sodium (metallic) has higher mp/bp than chlorine (simple molecular QB7Ch 4, 712mbrine electrolysis passage: explain why negative ions must not cross the membrane (NaOH pu QB8Ch 8, 108muse table of reaction times to show transition metal compounds are better catalysts than G QB9 eitherCh 810mdescribe experiments with dilute HCl to place metal M fourth in the reactivity series (mea QB9 orCh 10, 11, 1210mcracking dodecane: draw hexane and name/draw the other product (hexene)	1 marks R-ESTERUSES
2011Oct/Nov 2011	P1	old syl5067	Q1 C2Q2 C2Q3 C6Q4 C3Q5 C3Q6 C3Q7 C3Q8 C4Q9 C4Q10 C7Q11 C9Q12 C10Q13 C7Q14 C3Q15 C5Q16 C5Q17 C8Q18 C7Q19 C8Q20 C12Q21 C8Q22 C8Q23 C8Q24 C5Q25 C3Q26 C8Q27 C8Q28 C12Q29 C8Q30 C5Q31 C11Q32 C11Q33 C11Q34 C11Q35 C11Q36 C11Q37 C11Q38 C11Q39 C11Q40 C11	1 marks R-RECYCLEMETAL
2011Oct/Nov 2011	P2	old syl5067	QA1Ch 7, 124mpolluted-air gas cloud: pick CO as product of incomplete combustion QA2Ch 2, 3, 6, 77mcompare products of electrolysis of dilute aqueous KCl vs molten KCl QA3Ch 5, 107mname and formula of salt from CaCO3 + dilute HCl (calcium chloride) QA4Ch 36mdifference between simple molecular and giant molecular structures QA5Ch 3, 4, 99mtotal energy released by combusting 4 kg of ethyne (moles x 1300 kJ/mol) QA6Ch 4, 119mtwo physical property differences between cyclopentane and cycloheptane (gradation) QA7Ch 2, 3, 4, 58msimilarities and differences between nuclei of uranium isotopes U-234/235/238 QB8Ch 3, 412mshow 1 kg phenacite Be2SiO4 has larger mass of Si but more moles of Be atoms QB9Ch 4, 128mmass of CaCO3 needed to remove one tonne of SO2 QB10 eitherCh 810miron rod in aqueous Cu(II) ions: describe observations and explain displacement QB10 orCh 1110mdifferences between addition polymers (poly(propene)) and condensation polymers (nylon)	—
2010Oct/Nov 2010	P1	old syl5067	Q1 C2Q2 C6Q3 C2Q4 C3Q5 C4Q6 C8Q7 C3Q8 C4Q9 C7Q10 C7Q11 C9Q12 C9Q13 C10Q14 C5Q15 C7Q16 C7Q17 C5Q18 C10Q19 C5Q20 C5Q21 C4Q22 C8Q23 C8Q24 C8Q25 C8Q26 C8Q27 C8Q28 C8Q29 C8Q30 C5Q31 C8Q32 C12Q33 C12Q34 C11Q35 C11Q36 C11Q37 C11Q38 C11Q39 C11Q40 C11	1 marks R-BLASTFURNACE
2010Oct/Nov 2010	P2	old syl5067	Q1Ch 3, 85mperiodic table skeleton (H,N,Ne,Mg,S,K,Br): pick the elements forming basic oxides Q2Ch 3, 4, 116mpredict and explain lower softening temperature of low molecular mass poly(propene) Q3Ch 2, 56mexplain why NH4Cl white powder forms nearer HCl end: diffusion rate depends on molecular m Q4Ch 26mdefine the term isotope for 37Cl Q5Ch 4, 11, 129mmass of octane burned to produce 132 g CO2 from combustion equation Q6Ch 3, 4, 7, 810mcomplete oxidation state table for Al and Fe in Thermit reaction; oxidised or reduced Q7Ch 108msuggest method to follow rate of H2O2 decomposition (gas volume against time) QB8Ch 4, 510mconcentration of NaOH from pH-probe titration graph equivalence volume with 0.1 mol/dm3 HC QB9Ch 710mDowns-cell electrolysis of molten NaCl: anode half equation with state symbols and test fo QB10 eitherCh 910mhydrogen vs methanol fuel cells: energy per gram calculation, advantages/disadvantages, en QB10 orCh 4, 1110mempirical formula of ethyl butanoate and verification from percentage composition data	2 marks R-ESTERUSES
2009Oct/Nov 2009	P1	old syl5067	Q1 C2Q2 C6Q3 C1Q4 C2Q5 C1Q6 C2Q7 C3Q8 C8Q9 C3Q10 C7Q11 C4Q12 C4Q13 C4Q14 C7Q15 C7Q16 C9Q17 C10Q18 C7Q19 C7Q20 C5Q21 C5Q22 C5Q23 C5Q24 C8Q25 C8Q26 C8Q27 C8Q28 C8Q29 C8Q30 C8Q31 C8Q32 C12Q33 C1Q34 C11Q35 C11Q36 C11Q37 C11Q38 C11Q39 C11Q40 C11	2 marks R-BLASTFURNACE, R-STEELS
2009Oct/Nov 2009	P2	old syl5067	Q1Ch 2, 35midentify the metal from mp/bp and solid+molten electrical conductivity table Q2Ch 35mtrue/false statements about a covalent molecule (NCl3-type) from its dot-and-cross diagram Q3Ch 4, 7, 9, 1110mexplain why electrolysis of water is endothermic via bond breaking/making Q4Ch 119mcomplete table with name/condensed/displayed formula of propanoyl chloride in acyl chlorid Q5Ch 9, 11, 1211mdescribe fractional distillation separating petrol and diesel from crude oil Q6Ch 4, 510mstate essential conditions for Haber process manufacture of ammonia QB7Ch 4, 512mMgO-from-magnesite flow chart: name CO2 waste gas, alkali reactant, filtration step, equat QB8Ch 4, 118mnumber of carbon atoms in average polymer chain from relative molecular mass 10500 QB9 eitherCh 4, 7, 810mpredict observations when hydrogen is passed over heated CaO, CuO, PbO (reduction depends QB9 orCh 4, 710mmass of 4.8 cm3 of oxygen using molar volume 24 dm3 at rtp	2 marks R-HABERCOND

Each paper broken down question by question: Q1 Ch 1, 2 5m means question 1 drew on chapters 1 and 2 and was worth 5 marks. Hover a question for what it actually asked. For Paper 1 (multiple choice) each chip is one question and its chapter (Q3 C8 = Q3, chapter 8). In Section B, either/or alternatives of one question are listed separately, and choose-a-question items are marked optional.

Each cell is the number of questions on that topic in that year's Paper 1 (40 chemistry questions, 1 mark each). Only content a 2026 candidate can still be asked is counted; a cell with an orange underline also lost marks that year to content since cut from the syllabus (hover for the amount) and the bottom row totals them. Darker = heavier.

Topic	’09	’10	’11	’12	’13	’14	’15	’16	’17	’18	’19	’20	’21	’22	’23	’24	’25	SP ’24	Avg	Last 5	Share
1. Experimental ChemistryMatter - Structures and Properties (Topics 1-3)	3	·	·	1	2	2	3	1	1	2	n/a	4	1	2	3	5	5	3	2.2	3.2	6%
2. The Particulate Nature of MatterMatter - Structures and Properties (Topics 1-3)	3	2	2	2	2	2	·	2	2	2	n/a	3	3	2	3	3	2	2	2.2	2.6	6%
3. Chemical Bonding and StructureMatter - Structures and Properties (Topics 1-3)	2	2	6	5	3	5	9	4	4	4	n/a	2	4	3	5	4	3	6	4.1	3.8	11%
4. Chemical CalculationsChemical Reactions (Topics 4-10)	3	3	2	5	4	5	5	2	3	3	n/a	3	4	6	6	5	5	5	4.0	5.2	10%
5. Acid-Base ChemistryChemical Reactions (Topics 4-10)	4	5	4	3	4	2	4	3	5	3	n/a	4	2	5	2	2	5	3	3.6	3.2	9%
6. Qualitative AnalysisChemical Reactions (Topics 4-10)	1	1	1	2	1	1	1	3	2	1	n/a	1	2	1	3	2	1	1	1.5	1.8	4%
7. Redox ChemistryChemical Reactions (Topics 4-10)	5	4	3	5	4	4	3	4	5	5	n/a	3	3	3	5	5	5	4	4.1	4.2	11%
8. Patterns in the Periodic TableChemical Reactions (Topics 4-10)	7	9	7	4	9	7	5	8	6	7	n/a	4	7	3	5	3	4	4	5.9	4.4	15%
9. Chemical EnergeticsChemical Reactions (Topics 4-10)	1	2	1	1	1	·	3	1	1	3	n/a	2	2	2	2	2	1	2	1.6	1.8	4%
10. Rate of ReactionsChemical Reactions (Topics 4-10)	1	2	1	1	1	2	·	1	2	2	n/a	2	1	2	1	1	2	2	1.4	1.4	4%
11. Organic ChemistryChemistry in a Sustainable World (Topics 11-12)	7	7	10	7	7	6	5	8	7	6	n/a	7	8	7	4	7	5	7	6.8	6.2	18%
12. Maintaining Air QualityChemistry in a Sustainable World (Topics 11-12)	1	2	2	2	·	2	·	1	1	1	n/a	2	2	1	1	1	2	1	1.3	1.4	3%
Live total	38	39	39	38	38	38	38	38	39	39	n/a	37	39	37	40	40	40	40	38.6	39.2
Removed content (not counted)	2	1	1	2	2	2	2	2	1	1	n/a	3	1	3	·	·	·	·

SP columns are 2023-syllabus specimen papers — a guide to what the board intends, not a sitting; they are excluded from Avg, Last 5 and the forecast. · 2019: no paper in the archive.

Each cell is the number of marks on that topic in that year's Paper 2 (out of 80). Section B is choose-one-of-two, so each optional question counts half. Only content a 2027 candidate can still be asked is counted; a cell with an orange underline also lost marks that year to content since cut from the syllabus (hover for the amount) and the bottom row totals them. Darker = heavier.

Topic	’09	’10	’11	’12	’13	’14	’15	’16	’17	’18	’19	’20	’21	’22	’23	’24	’25	’26	SP ’24	Avg	Last 5	Share
1. Experimental ChemistryMatter - Structures and Properties (Topics 1-3)	·	·	·	·	4	·	·	·	·	2	n/a	4	·	2	·	·	1	·	2	0.8	0.6	1%
2. The Particulate Nature of MatterMatter - Structures and Properties (Topics 1-3)	1	9	4	3	·	1	1	1	·	3	n/a	·	·	7	7	·	7	6	8	2.9	5.4	4%
3. Chemical Bonding and StructureMatter - Structures and Properties (Topics 1-3)	9	6	15	6	6	13	2	4	6	8.5	n/a	19.5	6.5	6	3	18	15	14	3	9.3	11.2	12%
4. Chemical CalculationsChemical Reactions (Topics 4-10)	20	14	24	8	12	9	7	12	26.5	13	n/a	14	15	13	10	20	19	17	14	14.9	15.8	19%
5. Acid-Base ChemistryChemical Reactions (Topics 4-10)	9	8	5	10	5	12.5	7	14	·	7	n/a	5	11	·	3	11	6	2	2	6.8	4.4	9%
6. Qualitative AnalysisChemical Reactions (Topics 4-10)	·	·	1	·	4	·	·	3	1	6	n/a	·	1	·	4	·	·	·	·	1.2	0.8	2%
7. Redox ChemistryChemical Reactions (Topics 4-10)	6	13	4	9	15	11.5	13	6	6	7	n/a	6	8	15	13	9	6	10	9	9.3	10.6	12%
8. Patterns in the Periodic TableChemical Reactions (Topics 4-10)	2	5	5	15	9	5	15	13	11	12	n/a	2	6	11	11	7	4	2	18	7.9	7.0	10%
9. Chemical EnergeticsChemical Reactions (Topics 4-10)	5	5	1	4	2	11	4	·	5	2	n/a	6	5	4	6	1.5	4	4	2	4.1	3.9	5%
10. Rate of ReactionsChemical Reactions (Topics 4-10)	·	8	3	5.5	10	·	·	2	5.5	3	n/a	3	3.5	1	6	4	·	7	·	3.6	3.6	5%
11. Organic ChemistryChemistry in a Sustainable World (Topics 11-12)	22	7	12	11	3.5	17	18	16	11	8	n/a	12.5	14	15	10	9.5	16	10	15	12.5	12.1	16%
12. Maintaining Air QualityChemistry in a Sustainable World (Topics 11-12)	4	4	6	7.5	7.5	·	10	6	7	5	n/a	3	4	5	7	·	2	8	7	5.1	4.4	6%
Live total	78	79	80	79	78	80	77	77	79	76.5	n/a	75	74	79	80	80	80	80	80	78.3	79.8
Removed content (not counted)	2	1	·	1	2	·	3	3	1	3.5	n/a	5	6	1	·	·	·	·	·

SP columns are 2023-syllabus specimen papers — a guide to what the board intends, not a sitting; they are excluded from Avg, Last 5 and the forecast. · 2019: no paper in the archive.

Comparing 26 pre-2023 papers against 9 papers set on the 2023 syllabus. Share = percentage of live (non-removed) marks. A large positive shift means the new syllabus leans on that topic harder.

Topic	Pre-2023	2023 syl	Shift	Reading
2. The Particulate Nature of Matter	3.8%	6.8%	+3.0	heavier under the new syllabus
4. Chemical Calculations	15.6%	18.0%	+2.4	heavier under the new syllabus
3. Chemical Bonding and Structure	10.6%	12.7%	+2.0	heavier under the new syllabus
1. Experimental Chemistry	2.3%	3.4%	+1.1	broadly unchanged
7. Redox Chemistry	11.3%	11.8%	+0.5	broadly unchanged
10. Rate of Reactions	4.1%	4.1%	-0.0	broadly unchanged
6. Qualitative Analysis	2.3%	2.0%	-0.3	broadly unchanged
12. Maintaining Air Quality	5.7%	5.2%	-0.5	broadly unchanged
9. Chemical Energetics	4.9%	4.4%	-0.5	broadly unchanged
11. Organic Chemistry	17.2%	14.9%	-2.3	lighter under the new syllabus
8. Patterns in the Periodic Table	12.9%	10.4%	-2.5	lighter under the new syllabus
5. Acid-Base Chemistry	9.4%	6.4%	-3.0	lighter under the new syllabus

Dead content still sitting in your past papers

Marks per year that test content a 2026 candidate is no longer examined on — 42 sub-parts, 56 marks in total across the archive. If you drill these papers verbatim, this is the time you would waste.

Year	Dead marks	Live marks	Proportion wasted
2026	0	80	0.0%
2025	0	120	0.0%
2024	0	120	0.0%
2023	0	120	0.0%
2022	4	116	3.3%
2021	7	113	5.8%
2020	8	112	6.7%
2018	4.5	115.5	3.8%
2017	2	118	1.7%
2016	5	115	4.2%
2015	5	115	4.2%
2014	2	118	1.7%
2013	4	116	3.3%
2012	3	117	2.5%
2011	1	119	0.8%
2010	2	118	1.7%
2009	4	116	3.3%

Where each topic actually earns its marks. A topic that lives in P1 needs fast recognition; one that lives in P2 needs written explanation and working.

Topic	P1	P2	Balance	Dominant question styles
11. Organic Chemistry	112	220.5	34% P1	apply ×162 recall ×51 data-interpretation ×22
4. Chemical Calculations	64	253.5	20% P1	calculation ×115 apply ×76 data-interpretation ×12
8. Patterns in the Periodic Table	107	148.5	42% P1	apply ×117 recall ×45 data-interpretation ×31
3. Chemical Bonding and Structure	68	159.5	30% P1	apply ×86 extended-explanation ×31 recall ×22
7. Redox Chemistry	67	157.5	30% P1	apply ×111 extended-explanation ×18 recall ×14
5. Acid-Base Chemistry	60	120.5	33% P1	apply ×90 recall ×22 data-interpretation ×17
12. Maintaining Air Quality	21	86	20% P1	recall ×34 apply ×25 extended-explanation ×14
9. Chemical Energetics	25	69.5	26% P1	apply ×25 data-interpretation ×17 calculation ×9
2. The Particulate Nature of Matter	35	50	41% P1	apply ×48 data-interpretation ×6 recall ×6
10. Rate of Reactions	22	61.5	26% P1	data-interpretation ×21 apply ×12 extended-explanation ×11
1. Experimental Chemistry	35	13	73% P1	apply ×20 data-interpretation ×12 experimental-design ×9
6. Qualitative Analysis	24	20	55% P1	apply ×19 data-interpretation ×9 recall ×6

Every question is sorted into one of three levels of thinking, inferred from what it asks you to do. Marks here are live content only (removed / out-of-syllabus questions excluded), so they reflect what the next papers are likely to demand. Recall = state / name / define (recall); Knowledge & understanding = describe / explain / apply a concept (apply, extended-explanation); Handling information = interpret data, calculate, design, solve (data-interpretation, calculation, experimental-design). These approximate the O-Level assessment objectives — AO1 (recall + understanding) and AO2 (handling information). The level is inferred from question style, so treat these as close estimates, not the official mark scheme split.

Recall

11% of live marks
218.5 marks across the archive

Knowledge & understanding

63% of live marks
1221.5 marks across the archive

Handling information

26% of live marks
508.5 marks across the archive

By paper

The multiple-choice paper leans on recall and recognition; the structured paper is where data-handling and problem-solving marks live.

Level of thinking	P1 marks	% of P1	P2 marks	% of P2	Total	Share of all marks
Recall	91	15%	127.5	10%	218.5	11%
Knowledge & understanding	396	64%	825.5	62%	1221.5	63%
Handling information	130	21%	378.5	28%	508.5	26%
All questions	617	100%	1331.5	100%	1948.5

By year

How the balance of thinking has shifted over time — the bar shows each year's mix as a proportion, so you can see trends even though papers differ slightly in size. Marks are live content only, both papers combined.

Year	Recall	Know & und.	Handling	Total
2026	16	51	13	80
2025	24	71.5	24.5	120
2024	8	77	35	120
2023	8	82	30	120
2022	13	73	30	116
2021	9	74	30	113
2020	14	68	30	112
2018	8.5	81	26	115.5
2017	12	68	38	118
2016	8	78	29	115
2015	15	61.5	38.5	115
2014	11	83	24	118
2013	13	70.5	32.5	116
2012	14.5	70	32.5	117
2011	19.5	70	29.5	119
2010	10	75.5	32.5	118
2009	15	67.5	33.5	116

Colours: Recall Knowledge & understanding Handling information

By topic

Which chapters are recall-heavy versus which demand data-handling and problem-solving. Hover a bar for the marks in each level.

Topic	Recall	Know & und.	Handling
11. Organic Chemistry	58.5	221.5	40.5
4. Chemical Calculations	2	103	212.5
8. Patterns in the Periodic Table	34	150	46
7. Redox Chemistry	15	185.5	23
3. Chemical Bonding and Structure	25	176.5	21
5. Acid-Base Chemistry	19	122.5	31
12. Maintaining Air Quality	39	58	10
9. Chemical Energetics	3	51	40.5
2. The Particulate Nature of Matter	7	72	6
10. Rate of Reactions	8	39.5	36
1. Experimental Chemistry	1	21	26
6. Qualitative Analysis	7	21	16

Colours: Recall Knowledge & understanding Handling information

Paper 1 · multiple choice · 2026 paper. Forecast of how many questions each topic is worth out of 40: the recency-weighted average over all 16 sittings (half-life 6 years; 2023-syllabus papers ×1.6), counting only content a 2026 candidate can still be asked. The means are scaled up ×1.03 so they add to the full 40: older papers spent some marks on content since cut from the syllabus, and a 2026 paper will have none. Heaviest three: Organic Chemistry (6.4), Patterns in the Periodic Table (5.1), Chemical Calculations (4.7).

#	Topic	2026 forecast (questions)	Recent range	Last 8 sittings ’17’18’20’21’22’23’24’25	Trend	Reliability
1	11. Organic ChemistryChemistry in a Sustainable World (Topics 11-12)	6.4	4–8	76787475	▼	steady
2	8. Patterns in the Periodic TableChemical Reactions (Topics 4-10)	5.1	3–7	67473534	▼	steady
3	4. Chemical CalculationsChemical Reactions (Topics 4-10)	4.7	3–6	33346655	▲	steady
4	7. Redox ChemistryChemical Reactions (Topics 4-10)	4.5	3–5	55333555	▬	steady
5	3. Chemical Bonding and StructureMatter - Structures and Properties (Topics 1-3)	4.0	2–5	44243543	▬	steady
6	5. Acid-Base ChemistryChemical Reactions (Topics 4-10)	3.5	2–5	53425225	▬	moderate
7	1. Experimental ChemistryMatter - Structures and Properties (Topics 1-3)	3.1	1–5	12412355	▲	moderate
8	2. The Particulate Nature of MatterMatter - Structures and Properties (Topics 1-3)	2.4	2–3	22332332	▬	steady
9	9. Chemical EnergeticsChemical Reactions (Topics 4-10)	1.7	1–3	13222221	▬	steady
10	6. Qualitative AnalysisChemical Reactions (Topics 4-10)	1.7	1–3	21121321	▬	moderate
11	10. Rate of ReactionsChemical Reactions (Topics 4-10)	1.5	1–2	22212112	▬	steady
12	12. Maintaining Air QualityChemistry in a Sustainable World (Topics 11-12)	1.4	1–2	11221112	▬	moderate

Reliability: steady appeared in every recent sitting with a small spread; volatile swings a lot or skips years — treat its forecast as a guess. Trend ▲/▼ means a clear drift over the recent sittings (hover for the rate); ▬ means no clear direction.

The outcomes this paper keeps returning to

Learning outcomes ranked by how often (and how recently) they have been asked in Paper 1. These are the outcomes most likely to appear again.

LO	Topic	Learning outcome	Last 5 / all	Last seen	A recent example
4.2(f)	4. Chemical Calculations	stoichiometric reacting masses and gas volumes (24 dm3 at rtp); limiting reactants	5 / 42	2025	2025 Q33 — comparing average rates of three reactions producing CO2 given in mol/h, dm3/min and g/s
6(c)	6. Qualitative Analysis	gas tests: ammonia, CO2, chlorine, H2, O2, SO2	5 / 18	2025	2025 Q21 — identifying compound X: green precipitate with NaOH(aq) and a gas on heating that decolourises acidified KMnO4 (FeSO4)
7.1(b)	7. Redox Chemistry	define redox in terms of electron transfer and changes in oxidation state	5 / 21	2025	2025 Q22 — identifying which of four mixtures undergo redox reactions (ethanol + oxygen, molten PbO + carbon)
5.2(b)	5. Acid-Base Chemistry	general solubility rules for common salts	5 / 17	2025	2025 Q19 — choosing a method to prepare pure barium sulfate from dilute sulfuric acid and a barium compound
1.1(b)	1. Experimental Chemistry	suggest suitable apparatus for simple experiments incl. collection of gases, rates; also drying of gases (CaO, conc H2SO4, fused CaCl2)	5 / 14	2025	2025 Q2 — drying agent and collection method for ammonia gas (calcium oxide, upward delivery)
9(b)	9. Chemical Energetics	energy profile diagrams incl. enthalpy changes and activation energy	5 / 17	2025	2025 Q31 — interpreting an energy profile diagram as exothermic in terms of bond breaking and bond making
3.2(c)	3. Chemical Bonding and Structure	deduce electron arrangement in other covalent molecules	5 / 18	2025	2025 Q11 — electrons shared in CO2 molecules formed from complete combustion of 0.50 mol propane (Avogadro constant)
6(b)	6. Qualitative Analysis	anion tests: carbonate, chloride, iodide, nitrate, sulfate	4 / 16	2025	2025 Q16 — pH and barium nitrate test results for sodium hydrogen sulfate versus sodium sulfate
4.2(e)	4. Chemical Calculations	calculate empirical and molecular formulae	5 / 13	2025	2025 Q13 — empirical formula of hydrocarbon Z from 4.4 g CO2 and 2.7 g H2O on combustion
11.2(j)	11. Organic Chemistry	reactions of alkenes (ethene): combustion, polymerisation, addition with bromine and hydrogen; also steam	4 / 21	2024	2024 Q35 — identify X from ethene + steam -> ethanol -> ethanoic acid -> ethyl ethanoate and give its empirical formula
7.1(c)	7. Redox Chemistry	identify redox reactions (O/H gain-loss, electron gain-loss, oxidation state changes)	4 / 17	2025	2025 Q22 — identifying which of four mixtures undergo redox reactions (ethanol + oxygen, molten PbO + carbon)
8.4(a)	8. Patterns in the Periodic Table	reactivity series order (Ca,Cu,H,Fe,Pb,Mg,K,Ag,Na,Zn) by reactions with water/steam/dilute HCl; also reduction of oxides by C/H2	3 / 19	2025	2025 Q30 — correct statement about ease of extracting metals from their ores and the reactivity series
2.2(f)	2. The Particulate Nature of Matter	deduce numbers of protons, neutrons, electrons in atoms and ions	5 / 15	2025	2025 Q7 — protons, neutrons and electrons in O2-, F-, Ne and Na+ from nuclide notation
8.1(b)	8. Patterns in the Periodic Table	position of element related to proton number and electronic configuration	4 / 16	2025	2025 Q27 — property that decreases across Period 3 from sodium to argon (metallic character)
6(a)	6. Qualitative Analysis	NaOH(aq)/ammonia(aq) tests for cations: Al3+, NH4+, Ca2+, Cu2+, Fe2+, Fe3+, Zn2+	5 / 16	2025	2025 Q21 — identifying compound X: green precipitate with NaOH(aq) and a gas on heating that decolourises acidified KMnO4 (FeSO4)
7.1(d)	7. Redox Chemistry	KI(aq) and acidified KMnO4 as tests for oxidising/reducing agents via colour changes	4 / 13	2025	2025 Q23 — statements about KI and acidified KMnO4 as tests for oxidising and reducing agents

Asked before, then went quiet

Outcomes asked at least three times in this paper but absent from the last four of its 16 sittings. Examiners rotate their coverage, so these are worth a revisit — but a long gap is a prompt to revise, not a promise it is due.

LO	Topic	Learning outcome	Asked	Last seen
5.1(d)	5. Acid-Base Chemistry	characteristic properties of acids: reactions with metals, bases, carbonates to form salts	10×	2020 (5 sittings ago)
8.2(b)	8. Patterns in the Periodic Table	Group 17 halogens: diatomic non-metals, trends in colour/state, displacement reactions	11×	2021 (4 sittings ago)
7.1(a)	7. Redox Chemistry	define oxidation and reduction in terms of oxygen/hydrogen gain/loss	7×	2018 (6 sittings ago)
8.1(d)	8. Patterns in the Periodic Table	similarities between elements in same group in terms of electronic configuration	4×	2014 (10 sittings ago)
8.1(g)	8. Patterns in the Periodic Table	predict properties of Group 1 and Group 17 elements using the Periodic Table	8×	2020 (5 sittings ago)
11.2(a)	11. Organic Chemistry	homologous series: general formula, similar chemical properties, gradation in physical properties	8×	2020 (5 sittings ago)
3.2(a)	3. Chemical Bonding and Structure	formation of covalent bond by sharing electron pair; noble gas configuration	4×	2017 (7 sittings ago)
8.4(f)	8. Patterns in the Periodic Table	conditions for rusting (oxygen + water); barrier prevention methods; also galvanising	6×	2021 (4 sittings ago)
11.2(b)	11. Organic Chemistry	alkanes: saturated hydrocarbons CnH2n+2	6×	2021 (4 sittings ago)
12(g)	12. Maintaining Air Quality	carbon cycle: combustion, respiration, photosynthesis; regulation of atmospheric CO2	4×	2020 (5 sittings ago)

Paper 2 · structured · 2027 paper. Forecast of how many marks each topic is worth out of 80: the recency-weighted average over all 17 sittings (half-life 6 years; 2023-syllabus papers ×1.6), counting only content a 2027 candidate can still be asked. Heaviest three: Chemical Calculations (15.9), Organic Chemistry (12.3), Chemical Bonding and Structure (11.1).

#	Topic	2027 forecast (marks)	Recent range	Last 8 sittings ’18’20’21’22’23’24’25’26	Trend	Reliability
1	4. Chemical CalculationsChemical Reactions (Topics 4-10)	15.9	10–20	1314151310201917	▲	steady
2	11. Organic ChemistryChemistry in a Sustainable World (Topics 11-12)	12.3	8–16	812.51415109.51610	▬	steady
3	3. Chemical Bonding and StructureMatter - Structures and Properties (Topics 1-3)	11.1	3–19.5	8.519.56.563181514	▲	moderate
4	7. Redox ChemistryChemical Reactions (Topics 4-10)	9.5	6–15	76815139610	▬	steady
5	8. Patterns in the Periodic TableChemical Reactions (Topics 4-10)	7.0	2–12	12261111742	▼	moderate
6	5. Acid-Base ChemistryChemical Reactions (Topics 4-10)	6.0	0–11	7511·31162	▬	moderate
7	12. Maintaining Air QualityChemistry in a Sustainable World (Topics 11-12)	4.8	0–8	53457·28	▬	moderate
8	9. Chemical EnergeticsChemical Reactions (Topics 4-10)	4.1	1.5–6	265461.544	▬	moderate
9	2. The Particulate Nature of MatterMatter - Structures and Properties (Topics 1-3)	3.9	0–7	3··77·76	▲	volatile
10	10. Rate of ReactionsChemical Reactions (Topics 4-10)	3.8	0–7	333.5164·7	▬	moderate
11	6. Qualitative AnalysisChemical Reactions (Topics 4-10)	1.0	0–6	6·1·4···	▼	volatile
12	1. Experimental ChemistryMatter - Structures and Properties (Topics 1-3)	0.7	0–4	24·2··1·	▬	volatile

The outcomes this paper keeps returning to

Learning outcomes ranked by how often (and how recently) they have been asked in Paper 2. These are the outcomes most likely to appear again.

LO	Topic	Learning outcome	Last 5 / all	Last seen	A recent example
4.1(e)	4. Chemical Calculations	construct chemical equations with state symbols, including ionic equations	5 / 56	2026	2026 Q8(c) — overall equation for charging the battery by reversing the two electrode reactions (LiCoO2 -> Li + CoO2)
4.2(f)	4. Chemical Calculations	stoichiometric reacting masses and gas volumes (24 dm3 at rtp); limiting reactants	5 / 45	2026	2026 Q8(a)(i) — mass of CoO2 in a 30.0 g lithium-ion battery that is 15.0% cobalt by mass
7.2(f)	7. Redox Chemistry	predict products of electrolysis of an aqueous electrolyte	5 / 26	2026	2026 Q7(c)(i) — predict the mass of a 5.0 g copper positive electrode after 6 min (loses the 0.32 g plated at the cathode)
7.1(b)	7. Redox Chemistry	define redox in terms of electron transfer and changes in oxidation state	5 / 28	2026	2026 Q8(b) — lithium-ion battery discharging: element oxidised (Li 0 to +1) and element reduced (Co +4 to +3)
4.2(b)	4. Chemical Calculations	define relative molecular mass Mr; calculate Mr / relative formula mass	5 / 26	2026	2026 Q8(a)(i) — mass of CoO2 in a 30.0 g lithium-ion battery that is 15.0% cobalt by mass
4.2(g)	4. Chemical Calculations	solution concentration (mol/dm3, g/dm3); volumetric/titration calculations	3 / 20	2026	2026 Q7(b) — concentration of Cu2+ left at 2.5 min from the mass-of-copper graph (0.32 g Cu2+ in 50.0 cm3 at start)
10(a)	10. Rate of Reactions	effect of concentration, pressure, particle size, temperature on rate; collision theory explanation	4 / 21	2026	2026 Q6(c)(ii) — why ethene + steam needs 300 C and does not react at room temperature (particles lack activation energy)
8.4(b)	8. Patterns in the Periodic Table	reactivity as tendency to form positive ion; displacement from aqueous ions and oxides	4 / 24	2025	2025 Q5(c) — ionic equation with state symbols for Cu + Ag+ displacement (experiment 4)
3.2(c)	3. Chemical Bonding and Structure	deduce electron arrangement in other covalent molecules	5 / 18	2026	2026 Q9(b) — complete the dot-and-cross diagram of the PAA monomer C2H3COOH (C=C, C=O, O-H, outer electrons)
7.2(e)	7. Redox Chemistry	selective discharge: cations (reactivity series), anions (halide/hydroxide/sulfate), concentration effects	5 / 18	2026	2026 Q7(a) — electrolysis of dilute CuSO4(aq) with inert electrodes: appearance and pH once the copper-mass graph plateaus at 6 min (
2.2(f)	2. The Particulate Nature of Matter	deduce numbers of protons, neutrons, electrons in atoms and ions	3 / 16	2026	2026 Q3(d) — nuclide symbol of the selenium isotope with 41 neutrons formed when a bromine isotope breaks down (75/34 Se)
9(a)	9. Chemical Energetics	enthalpy change, exothermic (dH neg) / endothermic (dH pos)	4 / 22	2026	2026 Q6(c)(i) — complete energy profile diagram for exothermic ethene + steam with Ea and dH labelled
3.3(a)	3. Chemical Bonding and Structure	describe metals as lattice of positive ions in a sea of electrons	5 / 14	2026	2026 Q11(b) — how the giant ionic lattice of solid PbBr2 differs from a metallic lattice
12(g)	12. Maintaining Air Quality	carbon cycle: combustion, respiration, photosynthesis; regulation of atmospheric CO2	2 / 16	2026	2026 Q1(b)(ii) — carbon cycle: one process that removes CO2 from the atmosphere (photosynthesis)
5.1(b)	5. Acid-Base Chemistry	neutrality, relative acidity/alkalinity in terms of H+/OH- concentration, UI colour, pH scale	4 / 22	2026	2026 Q7(a) — electrolysis of dilute CuSO4(aq) with inert electrodes: appearance and pH once the copper-mass graph plateaus at 6 min (
4.1(b)	4. Chemical Calculations	deduce formulae of simple compounds from relative numbers of atoms and vice versa	4 / 15	2025	2025 Q8(c)(i) — suggest formula of antimony hydride from proton number 51

Asked before, then went quiet

Outcomes asked at least three times in this paper but absent from the last four of its 17 sittings. Examiners rotate their coverage, so these are worth a revisit — but a long gap is a prompt to revise, not a promise it is due.

LO	Topic	Learning outcome	Asked	Last seen
12(d)	12. Maintaining Air Quality	solutions: catalytic converters (redox), calcium carbonate for acid rain / flue gas desulfurisation	9×	2016 (9 sittings ago)
8.3(b)	8. Patterns in the Periodic Table	transition elements/compounds often act as catalysts	4×	2017 (8 sittings ago)
8.4(f)	8. Patterns in the Periodic Table	conditions for rusting (oxygen + water); barrier prevention methods; also galvanising	4×	2017 (8 sittings ago)
5.1(f)	5. Acid-Base Chemistry	importance of controlling soil pH; treating excess acidity with calcium hydroxide	5×	2020 (6 sittings ago)
1.1(b)	1. Experimental Chemistry	suggest suitable apparatus for simple experiments incl. collection of gases, rates; also drying of gases (CaO, conc H2SO4, fused CaCl2)	3×	2013 (12 sittings ago)
9(d)	9. Chemical Energetics	explain qualitatively overall enthalpy change via bond breaking/making	5×	2021 (5 sittings ago)
8.1(e)	8. Patterns in the Periodic Table	change from metallic to non-metallic character across a period	6×	2022 (4 sittings ago)
7.2(i)	7. Redox Chemistry	electroplating of metals and one use	4×	2020 (6 sittings ago)
11.2(k)	11. Organic Chemistry	meaning of polyunsaturated applied to food products	3×	2017 (8 sittings ago)
8.2(c)	8. Patterns in the Periodic Table	Group 18 noble gases: monoatomic, unreactive, uses in inert environments	3×	2018 (7 sittings ago)

What this is — and is not

A frequency model

The forecast says where the marks have been, weighted towards recent papers and the 2023 syllabus. It cannot see the next paper; treat it as a way to decide where to spend revision time, not as a leak.

Paper 1 and the structured paper differ

A topic can be a certainty in multiple choice and absent from long answers, or the reverse. That is why each paper is forecast on its own rather than blended.

Thin new-syllabus evidence

Only a handful of sittings exist under the 2023 syllabus, so the boost for those papers matters but cannot be proven. Re-run this report when more 2023-syllabus papers are available.

#	Topic	2026 forecast (questions)	Recent range	Last 8 sittings ’17’18’20’21’22’23’24’25	Trend	Reliability
1	11. Organic ChemistryChemistry in a Sustainable World (Topics 11-12)	6.4	4–8	76787475	▼	steady
2	8. Patterns in the Periodic TableChemical Reactions (Topics 4-10)	5.1	3–7	67473534	▼	steady
3	4. Chemical CalculationsChemical Reactions (Topics 4-10)	4.7	3–6	33346655	▲	steady
4	7. Redox ChemistryChemical Reactions (Topics 4-10)	4.5	3–5	55333555	▬	steady
5	3. Chemical Bonding and StructureMatter - Structures and Properties (Topics 1-3)	4.0	2–5	44243543	▬	steady
6	5. Acid-Base ChemistryChemical Reactions (Topics 4-10)	3.5	2–5	53425225	▬	moderate
7	1. Experimental ChemistryMatter - Structures and Properties (Topics 1-3)	3.1	1–5	12412355	▲	moderate
8	2. The Particulate Nature of MatterMatter - Structures and Properties (Topics 1-3)	2.4	2–3	22332332	▬	steady
9	9. Chemical EnergeticsChemical Reactions (Topics 4-10)	1.7	1–3	13222221	▬	steady
10	6. Qualitative AnalysisChemical Reactions (Topics 4-10)	1.7	1–3	21121321	▬	moderate
11	10. Rate of ReactionsChemical Reactions (Topics 4-10)	1.5	1–2	22212112	▬	steady
12	12. Maintaining Air QualityChemistry in a Sustainable World (Topics 11-12)	1.4	1–2	11221112	▬	moderate

The outcomes this paper keeps returning to

Learning outcomes ranked by how often (and how recently) they have been asked in Paper 1. These are the outcomes most likely to appear again.

LO	Topic	Learning outcome	Last 5 / all	Last seen	A recent example
4.2(f)	4. Chemical Calculations	stoichiometric reacting masses and gas volumes (24 dm3 at rtp); limiting reactants	5 / 42	2025	2025 Q33 — comparing average rates of three reactions producing CO2 given in mol/h, dm3/min and g/s
6(c)	6. Qualitative Analysis	gas tests: ammonia, CO2, chlorine, H2, O2, SO2	5 / 18	2025	2025 Q21 — identifying compound X: green precipitate with NaOH(aq) and a gas on heating that decolourises acidified KMnO4 (FeSO4)
7.1(b)	7. Redox Chemistry	define redox in terms of electron transfer and changes in oxidation state	5 / 21	2025	2025 Q22 — identifying which of four mixtures undergo redox reactions (ethanol + oxygen, molten PbO + carbon)
5.2(b)	5. Acid-Base Chemistry	general solubility rules for common salts	5 / 17	2025	2025 Q19 — choosing a method to prepare pure barium sulfate from dilute sulfuric acid and a barium compound
1.1(b)	1. Experimental Chemistry	suggest suitable apparatus for simple experiments incl. collection of gases, rates; also drying of gases (CaO, conc H2SO4, fused CaCl2)	5 / 14	2025	2025 Q2 — drying agent and collection method for ammonia gas (calcium oxide, upward delivery)
9(b)	9. Chemical Energetics	energy profile diagrams incl. enthalpy changes and activation energy	5 / 17	2025	2025 Q31 — interpreting an energy profile diagram as exothermic in terms of bond breaking and bond making
3.2(c)	3. Chemical Bonding and Structure	deduce electron arrangement in other covalent molecules	5 / 18	2025	2025 Q11 — electrons shared in CO2 molecules formed from complete combustion of 0.50 mol propane (Avogadro constant)
6(b)	6. Qualitative Analysis	anion tests: carbonate, chloride, iodide, nitrate, sulfate	4 / 16	2025	2025 Q16 — pH and barium nitrate test results for sodium hydrogen sulfate versus sodium sulfate
4.2(e)	4. Chemical Calculations	calculate empirical and molecular formulae	5 / 13	2025	2025 Q13 — empirical formula of hydrocarbon Z from 4.4 g CO2 and 2.7 g H2O on combustion
11.2(j)	11. Organic Chemistry	reactions of alkenes (ethene): combustion, polymerisation, addition with bromine and hydrogen; also steam	4 / 21	2024	2024 Q35 — identify X from ethene + steam -> ethanol -> ethanoic acid -> ethyl ethanoate and give its empirical formula
7.1(c)	7. Redox Chemistry	identify redox reactions (O/H gain-loss, electron gain-loss, oxidation state changes)	4 / 17	2025	2025 Q22 — identifying which of four mixtures undergo redox reactions (ethanol + oxygen, molten PbO + carbon)
8.4(a)	8. Patterns in the Periodic Table	reactivity series order (Ca,Cu,H,Fe,Pb,Mg,K,Ag,Na,Zn) by reactions with water/steam/dilute HCl; also reduction of oxides by C/H2	3 / 19	2025	2025 Q30 — correct statement about ease of extracting metals from their ores and the reactivity series
2.2(f)	2. The Particulate Nature of Matter	deduce numbers of protons, neutrons, electrons in atoms and ions	5 / 15	2025	2025 Q7 — protons, neutrons and electrons in O2-, F-, Ne and Na+ from nuclide notation
8.1(b)	8. Patterns in the Periodic Table	position of element related to proton number and electronic configuration	4 / 16	2025	2025 Q27 — property that decreases across Period 3 from sodium to argon (metallic character)
6(a)	6. Qualitative Analysis	NaOH(aq)/ammonia(aq) tests for cations: Al3+, NH4+, Ca2+, Cu2+, Fe2+, Fe3+, Zn2+	5 / 16	2025	2025 Q21 — identifying compound X: green precipitate with NaOH(aq) and a gas on heating that decolourises acidified KMnO4 (FeSO4)
7.1(d)	7. Redox Chemistry	KI(aq) and acidified KMnO4 as tests for oxidising/reducing agents via colour changes	4 / 13	2025	2025 Q23 — statements about KI and acidified KMnO4 as tests for oxidising and reducing agents

Asked before, then went quiet

LO	Topic	Learning outcome	Asked	Last seen
5.1(d)	5. Acid-Base Chemistry	characteristic properties of acids: reactions with metals, bases, carbonates to form salts	10×	2020 (5 sittings ago)
8.2(b)	8. Patterns in the Periodic Table	Group 17 halogens: diatomic non-metals, trends in colour/state, displacement reactions	11×	2021 (4 sittings ago)
7.1(a)	7. Redox Chemistry	define oxidation and reduction in terms of oxygen/hydrogen gain/loss	7×	2018 (6 sittings ago)
8.1(d)	8. Patterns in the Periodic Table	similarities between elements in same group in terms of electronic configuration	4×	2014 (10 sittings ago)
8.1(g)	8. Patterns in the Periodic Table	predict properties of Group 1 and Group 17 elements using the Periodic Table	8×	2020 (5 sittings ago)
11.2(a)	11. Organic Chemistry	homologous series: general formula, similar chemical properties, gradation in physical properties	8×	2020 (5 sittings ago)
3.2(a)	3. Chemical Bonding and Structure	formation of covalent bond by sharing electron pair; noble gas configuration	4×	2017 (7 sittings ago)
8.4(f)	8. Patterns in the Periodic Table	conditions for rusting (oxygen + water); barrier prevention methods; also galvanising	6×	2021 (4 sittings ago)
11.2(b)	11. Organic Chemistry	alkanes: saturated hydrocarbons CnH2n+2	6×	2021 (4 sittings ago)
12(g)	12. Maintaining Air Quality	carbon cycle: combustion, respiration, photosynthesis; regulation of atmospheric CO2	4×	2020 (5 sittings ago)

Paper 2 · structured · 2026 paper. Forecast of how many marks each topic is worth out of 80: the recency-weighted average over all 16 sittings (half-life 6 years; 2023-syllabus papers ×1.6), counting only content a 2026 candidate can still be asked. Heaviest three: Chemical Calculations (15.7), Organic Chemistry (12.8), Chemical Bonding and Structure (10.5).

#	Topic	2026 forecast (marks)	Recent range	Last 8 sittings ’17’18’20’21’22’23’24’25	Trend	Reliability
1	4. Chemical CalculationsChemical Reactions (Topics 4-10)	15.7	10–26.5	26.513141513102019	▬	steady
2	11. Organic ChemistryChemistry in a Sustainable World (Topics 11-12)	12.8	8–16	11812.51415109.516	▬	steady
3	3. Chemical Bonding and StructureMatter - Structures and Properties (Topics 1-3)	10.5	3–19.5	68.519.56.5631815	▲	moderate
4	7. Redox ChemistryChemical Reactions (Topics 4-10)	9.4	6–15	6768151396	▬	moderate
5	8. Patterns in the Periodic TableChemical Reactions (Topics 4-10)	8.1	2–12	111226111174	▼	moderate
6	5. Acid-Base ChemistryChemical Reactions (Topics 4-10)	6.8	0–11	·7511·3116	▬	volatile
7	12. Maintaining Air QualityChemistry in a Sustainable World (Topics 11-12)	4.1	0–7	753457·2	▬	moderate
8	9. Chemical EnergeticsChemical Reactions (Topics 4-10)	4.1	1.5–6	5265461.54	▬	moderate
9	2. The Particulate Nature of MatterMatter - Structures and Properties (Topics 1-3)	3.5	0–7	·3··77·7	▲	volatile
10	10. Rate of ReactionsChemical Reactions (Topics 4-10)	3.2	0–6	5.5333.5164·	▬	moderate
11	6. Qualitative AnalysisChemical Reactions (Topics 4-10)	1.2	0–6	16·1·4··	▬	volatile
12	1. Experimental ChemistryMatter - Structures and Properties (Topics 1-3)	0.8	0–4	·24·2··1	▬	volatile

The outcomes this paper keeps returning to

Learning outcomes ranked by how often (and how recently) they have been asked in Paper 2. These are the outcomes most likely to appear again.

LO	Topic	Learning outcome	Last 5 / all	Last seen	A recent example
4.1(e)	4. Chemical Calculations	construct chemical equations with state symbols, including ionic equations	5 / 54	2025	2025 Q10(a) — deduce limiting reactant for 1.0 g CaCO3 with 25.0 cm3 of 0.5 mol/dm3 HCl, with balanced equation
4.2(f)	4. Chemical Calculations	stoichiometric reacting masses and gas volumes (24 dm3 at rtp); limiting reactants	5 / 43	2025	2025 Q10(b) — percentage yield of CaCl2 from 0.6 g product
7.1(b)	7. Redox Chemistry	define redox in terms of electron transfer and changes in oxidation state	4 / 27	2025	2025 Q8(b)(iii) — identify chlorine as the other element changing oxidation state and give the change
4.2(g)	4. Chemical Calculations	solution concentration (mol/dm3, g/dm3); volumetric/titration calculations	3 / 19	2025	2025 Q10(a) — deduce limiting reactant for 1.0 g CaCO3 with 25.0 cm3 of 0.5 mol/dm3 HCl, with balanced equation
7.2(f)	7. Redox Chemistry	predict products of electrolysis of an aqueous electrolyte	5 / 24	2025	2025 Q5(e) — which of Zn/Cu/Pb/Ag are not discharged at the cathode from dilute aqueous salts, and why
4.2(b)	4. Chemical Calculations	define relative molecular mass Mr; calculate Mr / relative formula mass	5 / 24	2025	2025 Q7(c) — mass of hydrogen from 1 tonne methane in SMR allowing for 74% yield
8.4(b)	8. Patterns in the Periodic Table	reactivity as tendency to form positive ion; displacement from aqueous ions and oxides	5 / 24	2025	2025 Q5(c) — ionic equation with state symbols for Cu + Ag+ displacement (experiment 4)
7.2(e)	7. Redox Chemistry	selective discharge: cations (reactivity series), anions (halide/hydroxide/sulfate), concentration effects	5 / 17	2025	2025 Q5(e) — which of Zn/Cu/Pb/Ag are not discharged at the cathode from dilute aqueous salts, and why
4.1(b)	4. Chemical Calculations	deduce formulae of simple compounds from relative numbers of atoms and vice versa	4 / 15	2025	2025 Q8(c)(i) — suggest formula of antimony hydride from proton number 51
11.4(e)	11. Organic Chemistry	nylon (polyamide) and Terylene (polyester) as condensation polymers; partial structures	3 / 20	2025	2025 Q3(a)(ii) — draw the two monomers of the polyamide from its partial structure
9(a)	9. Chemical Energetics	enthalpy change, exothermic (dH neg) / endothermic (dH pos)	4 / 21	2025	2025 Q7(a) — draw energy profiles for endothermic SMR and exothermic WGS with Ea and dH labelled
10(a)	10. Rate of Reactions	effect of concentration, pressure, particle size, temperature on rate; collision theory explanation	4 / 18	2025	2025 Q10(c)(i) — why CaCO3 + dilute H2SO4 stops quickly and gives low yield (insoluble CaSO4 coats the lump)
3.2(c)	3. Chemical Bonding and Structure	deduce electron arrangement in other covalent molecules	5 / 16	2025	2025 Q2(b)(ii) — explain why nitrogen in NO does not achieve the usual noble gas octet
5.1(b)	5. Acid-Base Chemistry	neutrality, relative acidity/alkalinity in terms of H+/OH- concentration, UI colour, pH scale	4 / 21	2025	2025 Q8(b)(iv) — predict pH when SO2 dissolves in water and explain (acidic oxide)
3.3(a)	3. Chemical Bonding and Structure	describe metals as lattice of positive ions in a sea of electrons	4 / 12	2025	2025 Q1(c) — compare electrical conductivity of a metal and an ionic compound using structure
5.1(d)	5. Acid-Base Chemistry	characteristic properties of acids: reactions with metals, bases, carbonates to form salts	4 / 18	2025	2025 Q9(b)(i) — explain why 0.10 mol/dm3 H2SO4 needs half the titre of 0.10 mol/dm3 HCl (dibasic acid)

Asked before, then went quiet

LO	Topic	Learning outcome	Asked	Last seen
12(d)	12. Maintaining Air Quality	solutions: catalytic converters (redox), calcium carbonate for acid rain / flue gas desulfurisation	9×	2016 (8 sittings ago)
12(e)	12. Maintaining Air Quality	effects of pollutants on health/environment: toxic CO; NO2/SO2 acid rain effects	10×	2021 (4 sittings ago)
1.1(b)	1. Experimental Chemistry	suggest suitable apparatus for simple experiments incl. collection of gases, rates; also drying of gases (CaO, conc H2SO4, fused CaCl2)	3×	2013 (11 sittings ago)
8.3(b)	8. Patterns in the Periodic Table	transition elements/compounds often act as catalysts	4×	2017 (7 sittings ago)
8.4(f)	8. Patterns in the Periodic Table	conditions for rusting (oxygen + water); barrier prevention methods; also galvanising	4×	2017 (7 sittings ago)
5.1(f)	5. Acid-Base Chemistry	importance of controlling soil pH; treating excess acidity with calcium hydroxide	5×	2020 (5 sittings ago)
11.1(b)	11. Organic Chemistry	crude oil as hydrocarbon mixture; fractional distillation; fractions with competing uses	6×	2021 (4 sittings ago)
11.2(k)	11. Organic Chemistry	meaning of polyunsaturated applied to food products	3×	2017 (7 sittings ago)
9(d)	9. Chemical Energetics	explain qualitatively overall enthalpy change via bond breaking/making	5×	2021 (4 sittings ago)
7.2(i)	7. Redox Chemistry	electroplating of metals and one use	4×	2020 (5 sittings ago)

What this is — and is not

A frequency model

Paper 1 and the structured paper differ

A topic can be a certainty in multiple choice and absent from long answers, or the reverse. That is why each paper is forecast on its own rather than blended.

Thin new-syllabus evidence

Only a handful of sittings exist under the 2023 syllabus, so the boost for those papers matters but cannot be proven. Re-run this report when more 2023-syllabus papers are available.

General sentiments: the 2026 Paper 2

Paper6092/02Oct/Nov 2026

Total marks80as sat

Section A70 marksQ1–9 · compulsory

Section B10 marksanswer 1 of Q10 (10) / Q11 (10)

Questions119 compulsory + 2 Section B options

Sub-parts44marked parts, counting both Section B options

Marks by level of thinking (as sat)

Recall 16 (20%)Knowledge & understanding 51 (64%)Handling information 13 (16%)

Previous 8 sittings (2017–2025): Recall 7% · Knowledge & understanding 65% · Handling information 27%

Marks by question style (as sat)

apply 32.5extended-explanation 18.5recall 16calculation 12data-interpretation 1

An accessible Paper 2 built mostly on textbook contexts. Section A opens with three short questions that a prepared candidate should bank almost entirely: Q1 is 8 marks of straight recall on acid rain, the carbon cycle and global warming; Q2 asks about an enzyme as a catalyst and the effect of concentration on rate; Q3 is bromine isotopes and nuclide notation. Ethene + steam (Q6), electrolysis of copper(II) sulfate with a mass-time graph (Q7) and an addition polymer (Q9) are all familiar settings. The one long unfamiliar stem is Q8, a 12-mark information question on lithium-ion batteries, and even there every part maps onto a standard skill: a percentage-to-mass calculation, oxidation states, reversing two given electrode equations, graphite conducting, and lithium reacting with water.

Chemical calculations (Topic 4) again carry the most marks (17 of the 80 sat, all in Section A; 20 in 2024 and 19 in 2025), and this paper has four genuine calculations worth 12 marks: the total percentage of metal in PbCrO4, an empirical formula from 81.8% carbon, a Cu2+ concentration worked out from a graph reading, and the mass of CoO2 from a percentage. Bonding and structure is light in Section A (5 marks) but both Section B options are Topic 3, so every candidate sits at least 10 more marks of it. Air quality and rate come back strongly (8 and 7 marks) after being almost absent in 2025. The gaps are just as telling: no qualitative analysis, no experimental chemistry (apparatus, separation, purity, planning), no salt-preparation method (5.2 appears only as state symbols in 4(a)), no ammonia/Haber, no reactivity-series or rusting question, and only 2 marks on acids (the meaning of a weak acid and the formula of an anion).

By this project's tags, about a fifth of Section A (15 marks) is straight recall, about 45% (31 marks) is applying a standard idea to the given scenario, and calculation and extended explanation carry 12 marks each; there is no experimental-design work. The marks that separate candidates are the multi-step ones: seeing in 5(c) that C3H7 must be the alkane C6H14; reading the plateau in Figure 7.2 as 'every Cu2+ ion has been discharged' and turning a graph reading into a concentration in 7(a)-(b); predicting the copper anode's mass in 7(c); finding the oxidation state of cobalt in CoO2 and LiCoO2 in 8(b); explaining the small size of Li+ in 8(e), which is outside the explicit syllabus; and placing both double bonds in the acrylic-acid dot-and-cross in 9(b).

Difficulty

Easier than 2024 and a little kinder than 2025: the contexts are mostly familiar, recall rises to 15 Section A marks (2 in 2024, 13 in 2025), and the one long unfamiliar stem (Q8) asks only for standard skills. Against that, Section A has more calculation marks (12) than 2023, 2024 or 2025 (2, 8 and 3 by the same tags).

Section B

Both options are bonding and structure (Topic 3), so the choice is about the form of the question, not the topic. Q10 gives a table for element X (X2, mp -218 C, bp -183 C, covalent), SiO2 and NaCl: fill four gaps, predict the state and conductivity of SiO2 and NaCl at 1000 C (SiO2 still a non-conducting solid, NaCl a conducting liquid), then explain the melting-point difference between X and NaCl in terms of energy, bonds and forces. Q11 uses a labelled metallic-lattice diagram: explain a metal's high melting point, conductivity and malleability, describe how an alloy's structure differs, contrast solid PbBr2's ionic lattice with the metallic lattice, and use the table to show element Z (mp 1455 C, coloured compounds) is not in Group 1. Q11 is the kinder choice for a candidate who knows the standard structure explanations: almost every mark is a textbook sentence and the last 2 marks are read straight off the table. Q10 needs more judgement (checking 1000 C against two melting points and a boiling point, and keeping intermolecular forces apart from ionic bonds), so it suits stronger candidates.

The mix of question forms

Mostly short structured parts on prose stems: two tables to complete (6(b) bonds, 10(a) properties) and two data tables to use (8.1, 11.1), one plotted graph (Figure 7.2) with an apparatus diagram, four structure diagrams (Li-ion cell, graphite, PAA, metallic lattice), one energy profile to draw, one dot-and-cross to complete, two equation-writing parts (4(a), 8(c)), four calculations worth 12 marks and one 'a student states' evaluation (2(b)); there is no experimental planning.

Notable questions

Q4(b)'Total percentage by mass of metallic elements' is a trap: chromium is a metal (a transition element) as well as lead, so the answer is (207 + 52)/323 = 80.2%, not the 64.1% for lead alone.
Q5(c)The hardest 2 marks in Section A. No molecule can have the formula C3H7, so the hydrocarbon must be C6H14, an alkane, and aqueous bromine stays orange-brown. Candidates who see an odd number of hydrogens and guess 'unsaturated' lose both marks.
Q6(b)An unusual form: count every type of bond in ethene + water and in ethanol (C-C 1, C-H 5, C-O 1, O-H 1). It looks like the set-up for a bond-energy calculation, but no calculation follows; what it really tests is ethanol's displayed formula.
Q7(a)Links the graph to the chemistry. The flat line at 0.32 g from 6 minutes means every Cu2+ ion has been discharged, so the solution is colourless and acidic: H+ and SO4 2- are left behind as sulfuric acid once water/OH- is discharged at the anode. Answers of 'pale blue' or 'pH 7' miss the point.
Q7(b)A three-step calculation: read about 0.13 g of copper deposited at 2.5 minutes, take it away from the 0.32 g of Cu2+ present at the start, then convert the remaining 0.19 g to moles and divide by 0.0500 dm3 (about 0.058 mol/dm3).
Q8The 12-mark data-based question on lithium-ion batteries, with a full page of information, a cell diagram and both electrode equations. Every part is a standard skill in a new device, so candidates who read the stem calmly were well rewarded.
Q8(b)Needs the oxidation state of cobalt in two unfamiliar compounds: +4 in CoO2 and +3 in LiCoO2, while lithium goes from 0 to +1. Naming 'cobalt oxide' or oxygen as the element reduced is a likely way to lose marks.
Q8(e)Why Li+ is smaller than most other metal ions. Ionic size is not in the syllabus content; the expected reasoning is that Li+ has only one occupied electron shell. A genuine stretch item for 1 mark.
Q9(b)Dot-and-cross of the PAA monomer CH2=CH-COOH, with the three C circles and two O circles already drawn. Candidates must place both double bonds (C=C and C=O), the hydrogen on oxygen and the lone pairs on both oxygens, so 3 marks are easy to halve.
Q2(b)A 'student states' item whose answer, that enzymes denature above an optimum temperature, comes from biology; the chemistry syllabus only says enzymes are biological catalysts.

Where marks were lost

4(b): treating lead as the only metal (64.1%) instead of lead + chromium (80.2%).
5(b): rounding the C : H ratio of 1 : 2.67 to CH3 instead of multiplying by 3 to get C3H8, or forgetting to work out %H as 100 - 81.8.
5(c): calling C3H7 unsaturated and saying bromine is decolourised; the molecule is C6H14, an alkane.
6(c)(i): drawing the products above the reactants (that would be endothermic), or drawing the Ea and dH arrows from the wrong levels or pointing the wrong way.
7(a)-(b): saying the solution stays pale blue or becomes neutral; in 7(b), using the copper deposited (about 0.13 g) instead of the copper left in solution (about 0.19 g), or not converting 50.0 cm3 to 0.0500 dm3.
7(c)(i): assuming the copper anode keeps its 5.0 g or gains mass; it loses the same 0.32 g that is plated on the cathode (4.68 g).
8(b)-(c): naming 'cobalt oxide' or oxygen as the element reduced; leaving Li+ and e- uncancelled, or writing the discharging direction, in the charging equation LiCoO2 -> Li + CoO2.
10(c) and 11(b): writing 'intermolecular forces' for NaCl or PbBr2, saying covalent bonds break when X melts, or describing PbBr2 without oppositely charged ions held in fixed positions and no delocalised electrons.

Topical heat map of the 2026 Paper 2

Marks on each topic in the 2026 Paper 2 as a candidate sat it (Section A in full and each Section B option counted ×1/2, since a candidate answers 1 of 2), beside the average of the previous 8 sittings (2017–2025) and the forecast published on this site before the exam. Darker = heavier. Δ = paper minus forecast: blue the paper gave the topic more marks than forecast, orange fewer.

Topic	2026 paper	Prev 8 avg	Forecast	Δ vs forecast
1. Experimental Chemistry	·	1.1	0.8	-0.8
2. The Particulate Nature of Matter	6	3.0	3.5	+2.5
3. Chemical Bonding and Structure	14	10.3	10.5	+3.5
4. Chemical Calculations	17	16.3	15.7	+1.3
5. Acid-Base Chemistry	2	5.4	6.8	-4.8
6. Qualitative Analysis	·	1.5	1.2	-1.2
7. Redox Chemistry	10	8.8	9.4	+0.6
8. Patterns in the Periodic Table	2	8.0	8.1	-6.1
9. Chemical Energetics	4	4.2	4.1	-0.1
10. Rate of Reactions	7	3.2	3.2	+3.8
11. Organic Chemistry	10	12.0	12.8	-2.8
12. Maintaining Air Quality	8	4.1	4.1	+3.9
Total	80	77.9	80.0

The previous-sittings average adds to less than 80 because older papers spent marks on content since cut from the syllabus; those marks are not counted.

What the 2026 Paper 2 tested, outcome by outcome

Every learning outcome a marked part of the paper was tagged to, grouped by topic. The marks beside an outcome are the printed marks of the parts that test it (a part tagged to two outcomes counts for both); dashed question chips are Section B options, which not every candidate answered.

2. The Particulate Nature of Matter · 6 marks as sat · 6 outcomes

2.2(a) state relative charges and approximate relative masses of proton, neutron, electron 1mQ3(c)
2.2(b) describe atomic structure: nucleons in nucleus, electrons in shells 3mQ3(b) Q3(c) Q8(e)
2.2(c) define proton (atomic) number and nucleon (mass) number 2mQ3(d)
2.2(d) interpret and use nuclide notation 4mQ3(a) Q3(d)
2.2(e) define isotopes 3mQ3(a) Q3(b)
2.2(f) deduce numbers of protons, neutrons, electrons in atoms and ions 5mQ3(a) Q3(c) Q3(d)

3. Chemical Bonding and Structure · 14 marks as sat · 13 outcomes

3.1(a) formation of ions by electron loss/gain; noble gas configuration 1mQ8(e)
3.1(c) ionic materials contain giant lattice held by electrostatic attraction 6mQ10(a) Q11(b)
3.1(d) relate physical properties (incl. electrical) of ionic compounds to lattice structure 7mQ10(b) Q10(c)
3.2(b) dot-and-cross diagrams for covalent molecules e.g. H2, O2, H2O, CH4, CO2 3mQ9(b)
3.2(c) deduce electron arrangement in other covalent molecules 6mQ6(b) Q9(b)
3.2(d) relate physical properties (incl. electrical) of covalent substances to structure and bonding 3mQ10(c)
3.3(a) describe metals as lattice of positive ions in a sea of electrons 6mQ11(a)(i) Q11(b)
3.3(b) general physical properties of metals (high mp/bp, malleable, conductors); in terms of structure 3mQ11(a)(i)
3.4(b) describe an alloy as a mixture of metal with another element e.g. brass, stainless steel 2mQ11(a)(ii)
3.4(c) identify representations of metals and alloys from diagrams of structures 2mQ11(a)(ii)
3.4(e) compare structures: simple molecular, macromolecules, giant covalent (SiO2, diamond, graphite) to deduce properties 7mQ10(a) Q10(b)
3.4(f) compare bonding/structures of diamond and graphite; deduce properties and uses 1mQ8(d)
3.4(g) deduce physical and chemical properties from structure and bonding and vice versa 11mQ8(d) Q10(a) Q10(b) Q10(c)

4. Chemical Calculations · 17 marks as sat · 9 outcomes

4.1(c) deduce formulae of ionic compounds from charges on ions and vice versa 2mQ4(a)
4.1(e) construct chemical equations with state symbols, including ionic equations 4mQ4(a) Q8(c)
4.2(a) define relative atomic mass Ar 1mQ8(a)(ii)
4.2(b) define relative molecular mass Mr; calculate Mr / relative formula mass 6mQ4(b) Q8(a)(i)
4.2(c) define the mole in terms of the Avogadro constant 1mQ8(a)(ii)
4.2(d) calculate percentage mass of an element in a compound 6mQ4(b) Q8(a)(i)
4.2(e) calculate empirical and molecular formulae 5mQ5(b) Q5(c)
4.2(f) stoichiometric reacting masses and gas volumes (24 dm3 at rtp); limiting reactants 6mQ7(b) Q8(a)(i)
4.2(g) solution concentration (mol/dm3, g/dm3); volumetric/titration calculations 3mQ7(b)

5. Acid-Base Chemistry · 2 marks as sat · 4 outcomes

5.1(a) meanings of acid and alkali in terms of ions produced in aqueous solution and effect on Universal Indicator 1mQ9(c)(ii)
5.1(b) neutrality, relative acidity/alkalinity in terms of H+/OH- concentration, UI colour, pH scale 4mQ7(a)
5.1(c) qualitative difference between strong and weak acids in terms of extent of ionisation 1mQ9(c)(i)
5.2(b) general solubility rules for common salts 2mQ4(a)

7. Redox Chemistry · 10 marks as sat · 7 outcomes

7.1(b) define redox in terms of electron transfer and changes in oxidation state 3mQ8(b)
7.1(c) identify redox reactions (O/H gain-loss, electron gain-loss, oxidation state changes) 3mQ8(b)
7.2(e) selective discharge: cations (reactivity series), anions (halide/hydroxide/sulfate), concentration effects 4mQ7(a)
7.2(f) predict products of electrolysis of an aqueous electrolyte 5mQ7(a) Q7(c)(i)
7.2(g) construct ionic equations for electrode reactions 2mQ7(c)(ii)
7.2(h) electrolysis of CuSO4(aq) with copper electrodes as purification of copper 3mQ7(c)(i) Q7(c)(ii)
7.2(j) simple cells: electrical energy linked to reactivity series and redox 5mQ8(b) Q8(c)

8. Patterns in the Periodic Table · 2 marks as sat · 4 outcomes

8.1(b) position of element related to proton number and electronic configuration 1mQ8(e)
8.1(g) predict properties of Group 1 and Group 17 elements using the Periodic Table 1mQ8(f)
8.2(a) Group 1 alkali metals: soft, low density, trends in mp and reaction with water 3mQ8(f) Q11(c)
8.3(a) transition elements: high mp, high density, variable oxidation state, coloured compounds 2mQ11(c)

9. Chemical Energetics · 4 marks as sat · 3 outcomes

9(a) enthalpy change, exothermic (dH neg) / endothermic (dH pos) 3mQ6(c)(i)
9(b) energy profile diagrams incl. enthalpy changes and activation energy 4mQ6(c)(i) Q6(c)(ii)
9(c) bond breaking endothermic, bond making exothermic 1mQ6(c)(ii)

10. Rate of Reactions · 7 marks as sat · 4 outcomes

10(a) effect of concentration, pressure, particle size, temperature on rate; collision theory explanation 6mQ2(b) Q2(c) Q6(c)(ii)
10(b) define catalyst; effect of catalysts (incl. enzymes) on rate 4mQ2(a) Q2(b)
10(c) lower activation energy pathways account for rate increase 2mQ2(a)
10(d) compounds as industrial catalysts; enzymes as biological catalysts 2mQ2(a)

11. Organic Chemistry · 10 marks as sat · 11 outcomes

11.1(b) crude oil as hydrocarbon mixture; fractional distillation; fractions with competing uses 1mQ5(a)
11.2(b) alkanes: saturated hydrocarbons CnH2n+2 3mQ5(a) Q5(c)
11.2(e) alkanes generally unreactive except combustion and substitution by chlorine 1mQ9(a)(i)
11.2(g) draw/name alkenes (branched+unbranched C2-C4) 3mQ6(b)
11.2(i) saturated vs unsaturated hydrocarbons: molecular structure and aqueous bromine test 2mQ5(c)
11.2(j) reactions of alkenes (ethene): combustion, polymerisation, addition with bromine and hydrogen; also steam 1mQ6(a)
11.3(b) draw/name alcohols (branched+unbranched C1-C4) 3mQ6(b)
11.3(d) formation of ethanol: fermentation of glucose; also catalysed addition of steam to ethene 1mQ6(a)
11.3(g) carboxylic acids as weak acids reacting with carbonates, bases, some metals 1mQ9(c)(ii)
11.4(d) deduce structure of (addition) polymer from monomer and vice versa 3mQ9(b)
11.4(g) pollution problems from disposal of non-biodegradable plastics 3mQ9(a)(i) Q9(a)(ii)

12. Maintaining Air Quality · 8 marks as sat · 4 outcomes

12(b) common atmospheric pollutants: CO, methane, NO/NO2, ozone, SO2, unburned hydrocarbons 2mQ1(a)(i)
12(e) effects of pollutants on health/environment: toxic CO; NO2/SO2 acid rain effects 3mQ1(a)(i) Q1(a)(ii)
12(g) carbon cycle: combustion, respiration, photosynthesis; regulation of atmospheric CO2 3mQ1(b)(i) Q1(b)(ii)
12(h) CO2 and methane as greenhouse gases; sources; effects of increased levels (extreme weather, melting polar ice) 2mQ1(c)

No outcome at all from: 1. Experimental Chemistry; 6. Qualitative Analysis.

Comparison with our 2026 prediction

Against the forecast published on this site before the exam, the 2026 Paper 2 came within 1.5 marks of it on 5 of 12 topics, with a mean absolute error of 2.6 marks per topic (simply taking the average of the previous 8 sittings would have scored 2.5, and repeating 2025 exactly 2.8). The biggest misses: Patterns in the Periodic Table (forecast 8.1, paper 2); Acid-Base Chemistry (forecast 6.8, paper 2); Maintaining Air Quality (forecast 4.1, paper 8). 12 of the 16 outcomes on our “keeps returning” list were asked, and 2 of the 10 that had “gone quiet” came back. 9 outcomes came in cold (not in a Paper 2 for 5+ years, or never), and 5 of the 20 most heavily weighted outcomes were not asked at all.

Topic by topic

Topic and verdict	Forecast	2026 paper	Error
1. Experimental ChemistryOn target (a small forecast; the paper had none).	0.8	0	-0.8
2. The Particulate Nature of MatterUnder-predicted by 2.5, but inside its recent range (0–7).	3.5	6	+2.5
3. Chemical Bonding and StructureUnder-predicted by 3.5, but inside its recent range (3–19.5).	10.5	14	+3.5
4. Chemical CalculationsOn target.	15.7	17	+1.3
5. Acid-Base ChemistryWell over-predicted by 4.8, but inside its recent range (0–11).	6.8	2	-4.8
6. Qualitative AnalysisOn target (a small forecast; the paper had none).	1.2	0	-1.2
7. Redox ChemistryOn target.	9.4	10	+0.6
8. Patterns in the Periodic TableWell over-predicted by 6.1, but inside its recent range (2–12).	8.1	2	-6.1
9. Chemical EnergeticsOn target.	4.1	4	-0.1
10. Rate of ReactionsUnder-predicted by 3.8: more than in any of the previous 8 sittings.	3.2	7	+3.8
11. Organic ChemistryOver-predicted by 2.8, but inside its recent range (8–16).	12.8	10	-2.8
12. Maintaining Air QualityUnder-predicted by 3.9: more than in any of the previous 8 sittings.	4.1	8	+3.9
Mean absolute error			2.6

Error = paper minus forecast, in marks as sat. Over-predicted (forecast too high): Patterns in the Periodic Table; Acid-Base Chemistry; Organic Chemistry. Under-predicted (forecast too low): Maintaining Air Quality; Rate of Reactions; Chemical Bonding and Structure; The Particulate Nature of Matter. Within 1.5 marks counts as on target.

“Keeps returning”: did they come?

The 16 outcomes the forecast said Paper 2 keeps returning to. 12 were asked.

LO	Learning outcome	In the 2026 paper
4.1(e)	construct chemical equations with state symbols, including ionic equations	asked Q4(a) Q8(c)
4.2(f)	stoichiometric reacting masses and gas volumes (24 dm3 at rtp); limiting reactants	asked Q7(b) Q8(a)(i)
7.1(b)	define redox in terms of electron transfer and changes in oxidation state	asked Q8(b)
4.2(g)	solution concentration (mol/dm3, g/dm3); volumetric/titration calculations	asked Q7(b)
7.2(f)	predict products of electrolysis of an aqueous electrolyte	asked Q7(a) Q7(c)(i)
4.2(b)	define relative molecular mass Mr; calculate Mr / relative formula mass	asked Q4(b) Q8(a)(i)
8.4(b)	reactivity as tendency to form positive ion; displacement from aqueous ions and oxides	not asked
7.2(e)	selective discharge: cations (reactivity series), anions (halide/hydroxide/sulfate), concentration effects	asked Q7(a)
4.1(b)	deduce formulae of simple compounds from relative numbers of atoms and vice versa	not asked
11.4(e)	nylon (polyamide) and Terylene (polyester) as condensation polymers; partial structures	not asked
9(a)	enthalpy change, exothermic (dH neg) / endothermic (dH pos)	asked Q6(c)(i)
10(a)	effect of concentration, pressure, particle size, temperature on rate; collision theory explanation	asked Q2(b) Q2(c) Q6(c)(ii)
3.2(c)	deduce electron arrangement in other covalent molecules	asked Q6(b) Q9(b)
5.1(b)	neutrality, relative acidity/alkalinity in terms of H+/OH- concentration, UI colour, pH scale	asked Q7(a)
3.3(a)	describe metals as lattice of positive ions in a sea of electrons	asked Q11(a)(i) Q11(b)
5.1(d)	characteristic properties of acids: reactions with metals, bases, carbonates to form salts	not asked

“Went quiet”: which came back?

Outcomes asked repeatedly in Paper 2 that had dropped out of the recent sittings. 2 of 10 came back.

LO	Learning outcome	In the 2026 paper
12(d)	solutions: catalytic converters (redox), calcium carbonate for acid rain / flue gas desulfurisationBefore: 9× · last 2016	still quiet
12(e)	effects of pollutants on health/environment: toxic CO; NO2/SO2 acid rain effectsBefore: 10× · last 2021	came back Q1(a)(i) Q1(a)(ii)
1.1(b)	suggest suitable apparatus for simple experiments incl. collection of gases, rates; also drying of gases (CaO, conc H2SO4, fused CaCl2)Before: 3× · last 2013	still quiet
8.3(b)	transition elements/compounds often act as catalystsBefore: 4× · last 2017	still quiet
8.4(f)	conditions for rusting (oxygen + water); barrier prevention methods; also galvanisingBefore: 4× · last 2017	still quiet
5.1(f)	importance of controlling soil pH; treating excess acidity with calcium hydroxideBefore: 5× · last 2020	still quiet
11.1(b)	crude oil as hydrocarbon mixture; fractional distillation; fractions with competing usesBefore: 6× · last 2021	came back Q5(a)
11.2(k)	meaning of polyunsaturated applied to food productsBefore: 3× · last 2017	still quiet
9(d)	explain qualitatively overall enthalpy change via bond breaking/makingBefore: 5× · last 2021	still quiet
7.2(i)	electroplating of metals and one useBefore: 4× · last 2020	still quiet

Surprises

Came in cold

Outcomes the 2026 Paper 2 tested that had not been in a Paper 2 for 5+ years, or ever. Their recency weight was low, so the forecast gave them little.

LO	Learning outcome	Where in 2026
2.2(c)	define proton (atomic) number and nucleon (mass) numberBefore 2026: never in a Paper 2; Paper 1 last 2010	Q3(d)
4.2(c)	define the mole in terms of the Avogadro constantBefore 2026: never in a Paper 2; Paper 1 last 2025	Q8(a)(ii)
11.4(g)	pollution problems from disposal of non-biodegradable plasticsBefore 2026: never in a Paper 2; Paper 1 last 2009	Q9(a)(i) Q9(a)(ii)
2.2(a)	state relative charges and approximate relative masses of proton, neutron, electronBefore 2026: Paper 2 last 2010 (16 years before)	Q3(c)
3.3(b)	general physical properties of metals (high mp/bp, malleable, conductors); in terms of structureBefore 2026: Paper 2 last 2011 (15 years before)	Q11(a)(i)
11.2(e)	alkanes generally unreactive except combustion and substitution by chlorineBefore 2026: Paper 2 last 2012 (14 years before)	Q9(a)(i)
11.3(b)	draw/name alcohols (branched+unbranched C1-C4)Before 2026: Paper 2 last 2020 (6 years before)	Q6(b)
11.1(b)	crude oil as hydrocarbon mixture; fractional distillation; fractions with competing usesBefore 2026: Paper 2 last 2021 (5 years before)	Q5(a)
12(e)	effects of pollutants on health/environment: toxic CO; NO2/SO2 acid rain effectsBefore 2026: Paper 2 last 2021 (5 years before)	Q1(a)(i) Q1(a)(ii)

Heavily weighted, not asked

The top 20 outcomes of the recency-weighted ranking for Paper 2 (every sitting before 2026); these 5 did not appear. on our list = on the published “keeps returning” list.

Rank	LO	Learning outcome
7	8.4(b)	reactivity as tendency to form positive ion; displacement from aqueous ions and oxidesAsked 24× in Paper 2, last 2025 on our list
9	4.1(b)	deduce formulae of simple compounds from relative numbers of atoms and vice versaAsked 15× in Paper 2, last 2025 on our list
10	11.4(e)	nylon (polyamide) and Terylene (polyester) as condensation polymers; partial structuresAsked 20× in Paper 2, last 2025 on our list
16	5.1(d)	characteristic properties of acids: reactions with metals, bases, carbonates to form saltsAsked 18× in Paper 2, last 2025 on our list
19	11.2(a)	homologous series: general formula, similar chemical properties, gradation in physical propertiesAsked 26× in Paper 2, last 2024

Outcomes not tested in the 2026 Paper 2

89 of the 154 learning outcomes in the Pure Chemistry syllabus (58%) had no marked part of the 2026 Paper 2 on them, Section B options included. 66 of them are P1 regular (asked 3+ times in Paper 1 across the archive) and 1 are overdue (last seen in any paper 5+ years before 2026, or never; amber rows). Last seen counts every paper of this subject, Paper 1 and specimen papers included; P1 · P2 = how many times each outcome has been asked in each paper. These outcomes feed the Paper 1 specimen sets.

LO	Learning outcome	Last seen	P1 · P2
1. Experimental Chemistry — 8 of 8 not tested
1.1(a)	name appropriate apparatus for measurement of time, temperature, mass, volume (burettes, pipettes, measuring cylinders, gas syringes) P1 regular	2025	8 · 0
1.1(b)	suggest suitable apparatus for simple experiments incl. collection of gases, rates; also drying of gases (CaO, conc H2SO4, fused CaCl2) P1 regular	2025	15 · 3
1.2(a)	describe separation/purification methods: solvent+filtration+crystallisation/evaporation, distillation, fractional distillation, paper chromatography; also sublimation, separating funnel P1 regular	2025	11 · 6
1.2(b)	suggest suitable separation/purification methods for solid-solid, solid-liquid, liquid-liquid mixtures P1 regular	2025	11 · 3
1.2(c)	interpret paper chromatograms incl. comparison with known samples; Rf values P1 regular	2025	7 · 3
1.2(d)	explain need for locating agents in chromatography of colourless compounds P1 regular	2024	4 · 0
1.2(e)	deduce identity/purity of substances from melting point and boiling point data P1 regular	2024	5 · 2
1.2(f)	explain importance of measuring purity in everyday substances e.g. foodstuffs, drugs	2024	1 · 1
2. The Particulate Nature of Matter — 4 of 10 not tested
2.1(a)	describe solid/liquid/gas states and explain interconversion via kinetic particle theory and energy changes P1 regular	2025	5 · 9
2.1(b)	describe and explain evidence for movement of particles in liquids and gases (Brownian motion not required) P1 regular	2024	3 · 1
2.1(c)	explain everyday effects of diffusion in terms of particles P1 regular	2025	6 · 3
2.1(d)	effect of molecular mass and temperature on rate of diffusion P1 regular	2025	13 · 3
3. Chemical Bonding and Structure — 4 of 17 not tested
3.1(b)	dot-and-cross diagrams for ionic bonds between metals and non-metals e.g. NaCl, MgCl2	2024	1 · 2
3.2(a)	formation of covalent bond by sharing electron pair; noble gas configuration P1 regular	2025	4 · 8
3.4(a)	differences between elements, compounds and mixtures	2025	2 · 3
3.4(d)	explain why alloys have different physical properties to constituent elements P1 regular	2024	3 · 6
4. Chemical Calculations — 4 of 13 not tested
4.1(a)	state symbols of elements and formulae of compounds in syllabus	2024	0 · 6
4.1(b)	deduce formulae of simple compounds from relative numbers of atoms and vice versa P1 regular	2025	5 · 15
4.1(d)	interpret chemical equations with state symbols	2024	2 · 9
4.2(h)	calculate % yield and % purity P1 regular	2025	9 · 7
5. Acid-Base Chemistry — 10 of 14 not tested
5.1(d)	characteristic properties of acids: reactions with metals, bases, carbonates to form salts P1 regular	2025	11 · 18
5.1(e)	H+ + OH- -> H2O as neutralisation	2024	2 · 1
5.1(f)	importance of controlling soil pH; treating excess acidity with calcium hydroxide	2022	2 · 5
5.1(g)	characteristic properties of bases: reactions with acids and ammonium salts P1 regular	2024	9 · 10
5.1(h)	classify oxides as acidic, basic, amphoteric, neutral P1 regular	2025	15 · 11
5.2(a)	techniques for preparation, separation, purification of salts (precipitation, titration, acid + metal/insoluble base/insoluble carbonate) P1 regular	2025	11 · 8
5.2(c)	suggest a method of preparing a given salt from suitable starting materials P1 regular	2025	12 · 4
5.3(a)	use of nitrogen (from air) and hydrogen (from cracking) in manufacture of ammonia P1 regular	2024	3 · 4
5.3(b)	some reactions are reversible e.g. manufacture of ammonia P1 regular	2025	3 · 6
5.3(c)	interpret data on industrial conditions for reversible reactions e.g. Haber process (Le Chatelier not required)	2025	1 · 4
6. Qualitative Analysis — 3 of 3 not tested
6(a)	NaOH(aq)/ammonia(aq) tests for cations: Al3+, NH4+, Ca2+, Cu2+, Fe2+, Fe3+, Zn2+ P1 regular	2025	17 · 6
6(b)	anion tests: carbonate, chloride, iodide, nitrate, sulfate P1 regular	2025	17 · 5
6(c)	gas tests: ammonia, CO2, chlorine, H2, O2, SO2 P1 regular	2025	19 · 5
7. Redox Chemistry — 8 of 15 not tested
7.1(a)	define oxidation and reduction in terms of oxygen/hydrogen gain/loss P1 regular	2024	8 · 8
7.1(d)	KI(aq) and acidified KMnO4 as tests for oxidising/reducing agents via colour changes P1 regular	2025	13 · 3
7.2(a)	describe electrolysis of molten/aqueous electrolytes; chemical changes at electrodes P1 regular	2025	5 · 18
7.2(b)	electrolysis as evidence for ions (lattice when solid, mobile when molten/in solution) P1 regular	2023	4 · 2
7.2(c)	electrolysis of molten NaCl with inert electrodes P1 regular	2024	5 · 1
7.2(d)	predict products of electrolysis of molten binary ionic compound, inert electrodes P1 regular	2025	8 · 2
7.2(i)	electroplating of metals and one use	2024	1 · 7
7.2(k)	hydrogen as potential fuel; hydrogen fuel cell	2025	2 · 10
8. Patterns in the Periodic Table — 16 of 20 not tested
8.1(a)	Periodic Table as arrangement of elements in order of increasing proton number	2024	0 · 3
8.1(c)	relationship between outer electrons and ionic charge (first 20 elements) P1 regular	2025	8 · 8
8.1(d)	similarities between elements in same group in terms of electronic configuration P1 regular	2025	5 · 7
8.1(e)	change from metallic to non-metallic character across a period P1 regular	2025	8 · 6
8.1(f)	relationship between outer electrons and metallic/non-metallic character P1 regular	2025	3 · 4
8.2(b)	Group 17 halogens: diatomic non-metals, trends in colour/state, displacement reactions P1 regular	2024	11 · 21
8.2(c)	Group 18 noble gases: monoatomic, unreactive, uses in inert environments	2025	2 · 4
8.2(d)	lack of reactivity of noble gases in terms of electronic configuration	2025	2 · 3
8.3(b)	transition elements/compounds often act as catalysts P1 regular	2024	3 · 4
8.4(a)	reactivity series order (Ca,Cu,H,Fe,Pb,Mg,K,Ag,Na,Zn) by reactions with water/steam/dilute HCl; also reduction of oxides by C/H2 P1 regular	2025	21 · 12
8.4(b)	reactivity as tendency to form positive ion; displacement from aqueous ions and oxides P1 regular	2025	16 · 24
8.4(c)	deduce order of reactivity from experimental results P1 regular	2025	7 · 8
8.4(d)	action of heat on carbonates; thermal stability related to reactivity series P1 regular	2024	9 · 5
8.4(e)	ease of obtaining metals from ores related to position in reactivity series P1 regular	2025	12 · 7
8.4(f)	conditions for rusting (oxygen + water); barrier prevention methods; also galvanising P1 regular	2024	6 · 5
8.4(g)	sacrificial protection of iron by more reactive metal P1 regular	2024	8 · 4
9. Chemical Energetics — 1 of 4 not tested
9(d)	explain qualitatively overall enthalpy change via bond breaking/making P1 regular	2025	9 · 6
10. Rate of Reactions — 2 of 6 not tested
10(e)	suggest method to investigate effect of a variable on rate	2023	1 · 5
10(f)	interpret data from rate-of-reaction experiments P1 regular	2025	12 · 14
11. Organic Chemistry — 25 of 36 not tested
11.1(a)	natural gas (mainly methane) and crude oil as non-renewable energy sources	2024	0 · 1
11.1(c)	biofuel (bioethanol from sugarcane) as renewable alternative	2025	1 · 3
11.1(d)	biofuel vs fossil fuels: environmental sustainability via CO2 offset	2024	0 · 4
11.2(a)	homologous series: general formula, similar chemical properties, gradation in physical properties P1 regular	2024	9 · 29
11.2(c)	draw/name alkanes (branched+unbranched C1-C4)	2024	0 · 3
11.2(d)	define isomerism and identify isomers P1 regular	2025	14 · 14
11.2(f)	alkenes: unsaturated hydrocarbons CnH2n P1 regular	2025	7 · 1
11.2(h)	manufacture of alkenes and hydrogen by cracking; why cracking is essential P1 regular	2025	4 · 13
11.2(k)	meaning of polyunsaturated applied to food products overdue	2017	1 · 3
11.2(l)	manufacture of margarine by addition of hydrogen to unsaturated vegetable oils P1 regular	2024	3 · 2
11.3(a)	alcohols as homologous series containing -OH P1 regular	2025	3 · 5
11.3(c)	reactions of alcohols: combustion, oxidation to carboxylic acids P1 regular	2025	17 · 5
11.3(e)	carboxylic acids as homologous series containing -CO2H P1 regular	2024	7 · 1
11.3(f)	draw/name carboxylic acids C1-C4 P1 regular	2025	8 · 3
11.3(h)	formation of ethanoic acid by oxidation of ethanol (atmospheric O2 or acidified KMnO4) P1 regular	2025	4 · 9
11.3(i)	reaction of carboxylic acid with alcohol to form ester e.g. ethyl ethanoate P1 regular	2025	17 · 13
11.3(j)	deduce name/formula of ester from carboxylic acid C1-C4 + alcohol C1-C4 and vice versa P1 regular	2025	8 · 9
11.4(a)	polymers as large molecules built from monomers P1 regular	2024	4 · 7
11.4(b)	formation of poly(ethene) as addition polymerisation P1 regular	2024	10 · 8
11.4(c)	uses of poly(ethene) e.g. plastic bags, clingfilm P1 regular	2024	3 · 2
11.4(e)	nylon (polyamide) and Terylene (polyester) as condensation polymers; partial structures P1 regular	2025	16 · 20
11.4(f)	uses of man-made fibres nylon and Terylene	2024	2 · 0
11.4(h)	two methods of recycling plastics: physical (melting to pellets), chemical (cracking to fuel; also depolymerisation to feedstock)	2025	1 · 1
11.4(i)	depolymerisation: polymers broken to monomers, e.g. acid hydrolysis of polyesters	2025	2 · 2
11.4(j)	social, economic, environmental issues of recycling plastics	2025	0 · 1
12. Maintaining Air Quality — 4 of 8 not tested
12(a)	volume composition of dry air (78% N2, 21% O2, noble gases mainly Ar, CO2) P1 regular	2025	3 · 8
12(c)	sources of pollutants: CO (incomplete combustion), NOx (lightning, engines), SO2 (volcanoes, fossil fuels) P1 regular	2025	5 · 14
12(d)	solutions: catalytic converters (redox), calcium carbonate for acid rain / flue gas desulfurisation P1 regular	2024	12 · 11
12(f)	importance of ozone layer; depletion by CFCs P1 regular	2025	4 · 4

Model answers to the 2026 Paper 2

Cambridge has not released its mark scheme yet, so these are teacher-written model answers, not the official scheme. Each part gives the mark points, working for calculations, and the textbook passage quoted word for word with its page, so you can learn the exact scientific wording. Concepts the paper tests that the textbook does not cover are flagged at the top.

Open full screen Download PDF

Paper 1 specimen sets

Ten Paper 1 (multiple-choice) sets in the layout and conventions of the real paper. Paper 1 for 2026 is still to come, so these are practice for it. Sets 1-4 are built from the outcomes the 2026 Paper 2 did not test (the “Not tested in 2026” tab); sets 5-10 cover the whole syllabus, graded by difficulty (sets 5-6 Easy, sets 7-8 Medium, sets 9-10 Hard). They are original questions, not the real paper. Each set has its full mark scheme, so you can mark yourself afterwards.

Outcomes the 2026 paper did not testWhole syllabus, graded by difficulty

Easy / Medium / Hard: every question is labelled.

Easy level · 40 multiple-choice questions · 1 hour · 40 marks · Easy 22, Medium 17, Hard 1Open full screen

Mark scheme (full answers)Open mark scheme

Medium level · 40 multiple-choice questions · 1 hour · 40 marks · Easy 17, Medium 19, Hard 4Open full screen

Mark scheme (full answers)Open mark scheme

Easy level · 40 multiple-choice questions · 1 hour · 40 marks · Easy 19, Medium 19, Hard 2Open full screen

Mark scheme (full answers)Open mark scheme

Medium level · 40 multiple-choice questions · 1 hour · 40 marks · Easy 14, Medium 22, Hard 4Open full screen

Mark scheme (full answers)Open mark scheme

Easy level · 40 multiple-choice questions · 1 hour · 40 marks · Easy 24, Medium 12, Hard 4Open full screen

Mark scheme (full answers)Open mark scheme

Easy level · 40 multiple-choice questions · 1 hour · 40 marks · Easy 24, Medium 12, Hard 4Open full screen

Mark scheme (full answers)Open mark scheme

Medium level · 40 multiple-choice questions · 1 hour · 40 marks · Easy 10, Medium 20, Hard 10Open full screen

Mark scheme (full answers)Open mark scheme

Medium level · 40 multiple-choice questions · 1 hour · 40 marks · Easy 10, Medium 20, Hard 10Open full screen

Mark scheme (full answers)Open mark scheme

Hard level · 40 multiple-choice questions · 1 hour · 40 marks · Easy 4, Medium 12, Hard 24Open full screen

Mark scheme (full answers)Open mark scheme

Hard level · 40 multiple-choice questions · 1 hour · 40 marks · Easy 4, Medium 12, Hard 24Open full screen

Mark scheme (full answers)Open mark scheme

Specimen Paper 2 built to the 2026 forecast (the forecast published before the 2026 exams; the Prediction tab has since moved on to the next sitting). They are not the 2026 papers: they reproduce the expected mix of topics and learning outcomes with original questions, in the layout, wording and mark conventions of the real papers (Paper 2 is 80 marks; the Paper 1 practice sets are on the 2026 P2 Analysis tab). It includes the Periodic Table. Sit them under timed conditions, then check where you lost marks. Each paper has its full mark scheme on its tab, so you can mark yourself afterwards.

80 marks · 1 hour 45 minutes · Section A compulsory, Section B: answer one questionOpen full screen

Mark scheme (full answers)Open mark scheme

How this paper follows the forecast

Topic by topic: what the 2026 forecast expected, and what this specimen contains. Paper 2 counts Section A in full and one Section B option (the two options are built in parallel, so each counts half).

Topic	2026 forecast (marks)	In this paper	Where
4. Chemical Calculations	15.7	16	Q3 (9), Q4 (2), Q6 (2), Q7 (1), Q8 (2)
11. Organic Chemistry	12.8	13	Q5 (8), Q8 (5)
3. Chemical Bonding and Structure	10.5	11	Q1 (8), Q2 (3)
7. Redox Chemistry	9.4	9	Q7 (4), Q9 (5), Q10 (5)
8. Patterns in the Periodic Table	8.1	8	Q7 (3), Q9 (5), Q10 (5)
5. Acid-Base Chemistry	6.8	7	Q4 (7)
12. Maintaining Air Quality	4.1	4	Q8 (4)
9. Chemical Energetics	4.1	4	Q6 (4)
2. The Particulate Nature of Matter	3.5	3	Q2 (3)
10. Rate of Reactions	3.2	3	Q6 (3)
6. Qualitative Analysis	1.2	1	Q7 (1)
1. Experimental Chemistry	0.8	1	Q2 (1)

Specimen Paper 1 built to the 2026 forecast (the forecast published before the 2026 exams; the Prediction tab has since moved on to the next sitting). They are not the 2026 papers: they reproduce the expected mix of topics and learning outcomes with original questions, in the layout, wording and mark conventions of the real papers (Paper 1 has 40 multiple-choice questions; the five newer Paper 1 practice sets are on the 2026 P2 Analysis tab). It includes the Periodic Table. Sit them under timed conditions, then check where you lost marks. Each paper has its full mark scheme on its tab, so you can mark yourself afterwards.

40 multiple-choice questions · 1 hour · 40 marksOpen full screen

Mark scheme (full answers)Open mark scheme

How this paper follows the forecast

Topic by topic: what the 2026 forecast expected, and what this specimen contains.

Topic	2026 forecast (questions)	In this paper	Where
11. Organic Chemistry	6.4	6	Q34, Q35, Q36, Q37, Q38, Q39
8. Patterns in the Periodic Table	5.1	5	Q25, Q26, Q27, Q28, Q29
4. Chemical Calculations	4.7	5	Q10, Q11, Q12, Q13, Q14
7. Redox Chemistry	4.5	4	Q21, Q22, Q23, Q24
3. Chemical Bonding and Structure	4.0	4	Q6, Q7, Q8, Q9
5. Acid-Base Chemistry	3.5	4	Q15, Q16, Q17, Q18
1. Experimental Chemistry	3.1	3	Q1, Q2, Q3
2. The Particulate Nature of Matter	2.4	2	Q4, Q5
9. Chemical Energetics	1.7	2	Q30, Q31
6. Qualitative Analysis	1.7	2	Q19, Q20
10. Rate of Reactions	1.5	2	Q32, Q33
12. Maintaining Air Quality	1.4	1	Q40

Printable priority order. Work top-down: topics are sorted by their forecast share of the 120 marks across Paper 1 and Paper 2 at their next sittings (Paper 1 2026, Paper 2 2027) (see the 2027 prediction tab for each paper on its own), and within each topic the cold outcomes are the ones most likely to catch you out.

1. Chemical Calculations — about 21 of 120 marks · ≈4.7 P1 questions + ≈15.9 P2 marks

Formulae and Equation Writing · The Mole Concept and Stoichiometry

2. Organic Chemistry — about 19 of 120 marks · ≈6.4 P1 questions + ≈12.3 P2 marks

Fuels and Crude Oil · Hydrocarbons · Alcohols, Carboxylic Acids and Esters · Polymers

Do not skip:

11.2(k) meaning of polyunsaturated applied to food products (last seen 2017 — 9 years cold)
11.1(a) natural gas (mainly methane) and crude oil as non-renewable energy sources (only 1 appearance ever)
11.4(j) social, economic, environmental issues of recycling plastics (only 1 appearance ever)
11.4(f) uses of man-made fibres nylon and Terylene (only 2 appearances ever)

3. Chemical Bonding and Structure — about 15 of 120 marks · ≈4.0 P1 questions + ≈11.1 P2 marks

Ionic Bonding · Covalent Bonding · Metallic Bonding · Structure and Properties of Materials

4. Redox Chemistry — about 14 of 120 marks · ≈4.5 P1 questions + ≈9.5 P2 marks

Oxidation and Reduction · Electrochemistry

5. Patterns in the Periodic Table — about 12 of 120 marks · ≈5.1 P1 questions + ≈7.0 P2 marks

Periodic Trends · Group Properties · Transition Elements · Reactivity Series

6. Acid-Base Chemistry — about 9 of 120 marks · ≈3.5 P1 questions + ≈6.0 P2 marks

Acids and Bases · Salts · Ammonia

7. The Particulate Nature of Matter — about 6 of 120 marks · ≈2.4 P1 questions + ≈3.9 P2 marks

Kinetic Particle Theory · Atomic Structure

8. Maintaining Air Quality — about 6 of 120 marks · ≈1.4 P1 questions + ≈4.8 P2 marks

Maintaining Air Quality

9. Chemical Energetics — about 6 of 120 marks · ≈1.7 P1 questions + ≈4.1 P2 marks

Chemical Energetics

10. Rate of Reactions — about 5 of 120 marks · ≈1.5 P1 questions + ≈3.8 P2 marks

Rate of Reactions

11. Experimental Chemistry — about 4 of 120 marks · ≈3.1 P1 questions + ≈0.7 P2 marks

Experimental Design · Methods of Purification and Analysis

Do not skip:

1.2(f) explain importance of measuring purity in everyday substances e.g. foodstuffs, drugs (only 2 appearances ever)

12. Qualitative Analysis — about 3 of 120 marks · ≈1.7 P1 questions + ≈1.0 P2 marks

Qualitative Analysis

Data caveats: 2016 P1.json — see the JSON notes field for detail.

O-Level Pure Chemistry — Theory Papers (P1 & P2)

Dead content still sitting in your past papers

Recall

Knowledge & understanding

Handling information

By paper

By year

By topic

The outcomes this paper keeps returning to

Asked before, then went quiet

The outcomes this paper keeps returning to

Asked before, then went quiet

What this is — and is not

A frequency model

Paper 1 and the structured paper differ

Thin new-syllabus evidence

The outcomes this paper keeps returning to

Asked before, then went quiet

The outcomes this paper keeps returning to

Asked before, then went quiet

What this is — and is not

A frequency model

Paper 1 and the structured paper differ

Thin new-syllabus evidence

General sentiments: the 2026 Paper 2

Difficulty

Section B

The mix of question forms

Notable questions

Where marks were lost

Topical heat map of the 2026 Paper 2

What the 2026 Paper 2 tested, outcome by outcome

2. The Particulate Nature of Matter · 6 marks as sat · 6 outcomes

3. Chemical Bonding and Structure · 14 marks as sat · 13 outcomes

4. Chemical Calculations · 17 marks as sat · 9 outcomes

5. Acid-Base Chemistry · 2 marks as sat · 4 outcomes

7. Redox Chemistry · 10 marks as sat · 7 outcomes

8. Patterns in the Periodic Table · 2 marks as sat · 4 outcomes

9. Chemical Energetics · 4 marks as sat · 3 outcomes

10. Rate of Reactions · 7 marks as sat · 4 outcomes

11. Organic Chemistry · 10 marks as sat · 11 outcomes

12. Maintaining Air Quality · 8 marks as sat · 4 outcomes

Comparison with our 2026 prediction

Topic by topic

“Keeps returning”: did they come?

“Went quiet”: which came back?

Surprises

Came in cold

Heavily weighted, not asked

Outcomes not tested in the 2026 Paper 2

Model answers to the 2026 Paper 2

Paper 1 specimen sets

Paper 1 · set 1 (Easy): coming soon

Paper 1 · set 2 (Medium): coming soon

Paper 1 · set 3 (Easy): coming soon

Paper 1 · set 4 (Medium): coming soon

Paper 1 · set 5 (Easy): coming soon

Paper 1 · set 6 (Easy): coming soon

Paper 1 · set 7 (Medium): coming soon

Paper 1 · set 8 (Medium): coming soon

Paper 1 · set 9 (Hard): coming soon

Paper 1 · set 10 (Hard): coming soon

How this paper follows the forecast

How this paper follows the forecast

1. Chemical Calculations — about 21 of 120 marks · ≈4.7 P1 questions + ≈15.9 P2 marks

2. Organic Chemistry — about 19 of 120 marks · ≈6.4 P1 questions + ≈12.3 P2 marks

3. Chemical Bonding and Structure — about 15 of 120 marks · ≈4.0 P1 questions + ≈11.1 P2 marks

4. Redox Chemistry — about 14 of 120 marks · ≈4.5 P1 questions + ≈9.5 P2 marks

5. Patterns in the Periodic Table — about 12 of 120 marks · ≈5.1 P1 questions + ≈7.0 P2 marks

6. Acid-Base Chemistry — about 9 of 120 marks · ≈3.5 P1 questions + ≈6.0 P2 marks

7. The Particulate Nature of Matter — about 6 of 120 marks · ≈2.4 P1 questions + ≈3.9 P2 marks

8. Maintaining Air Quality — about 6 of 120 marks · ≈1.4 P1 questions + ≈4.8 P2 marks

9. Chemical Energetics — about 6 of 120 marks · ≈1.7 P1 questions + ≈4.1 P2 marks

10. Rate of Reactions — about 5 of 120 marks · ≈1.5 P1 questions + ≈3.8 P2 marks

11. Experimental Chemistry — about 4 of 120 marks · ≈3.1 P1 questions + ≈0.7 P2 marks

12. Qualitative Analysis — about 3 of 120 marks · ≈1.7 P1 questions + ≈1.0 P2 marks