What you’ll learn16 learning objectivesChoose one objective for a focused lesson, or study the complete topic.3.2.1Oxidation and reduction• Electron transfer, oxidation state change• Oxygen gain/loss, hydrogen loss/gain• Oxidizing/reducing agents• Deduce oxidation states and identify oxidized/reduced speciesSyllabus objective3.2.2Half-equations• Separate oxidation and reduction• Show electron loss/gain• Deduce redox half-equations and equations in acidic or neutral solutionsSyllabus objective3.2.3Periodic trends in redox• Metals: ease of oxidation• Halogens: ease of reduction• Metal displacement reactions• Predict metal oxidation and halogen reduction using supplied dataSyllabus objective3.2.4Acids with reactive metals• Release H₂ gas• Deduce equations for reactive metals with dilute acidsSyllabus objective3.2.5Electrodes in electrochemical cells• Oxidation at anode• Reduction at cathode• Signs/polarities in voltaic vs. electrolytic cells• Identify anode/cathode from electrode reactionsSyllabus objective3.2.6Primary (voltaic) cells• Spontaneous redox → electrical energy• Electron flow: anode → cathode (external circuit)• Ion movement across salt bridge• Include metal/metal ion half-cells, circuit, and salt bridgeSyllabus objective3.2.7Secondary (rechargeable) cells• Redox reactions reversible with electrical energy• Deduce charging reactions from discharge reactions and compare cell typesSyllabus objective3.2.8Electrolytic cells• Electrical energy → chemical energy• Non-spontaneous reactions• Electrolysis of molten salts• Explain current conduction and deduce molten salt electrolysis productsSyllabus objective3.2.9Oxidation of organic functional groups• Primary alcohols → aldehydes → carboxylic acids• Secondary alcohols → ketones• Include distillation/reflux setup and that tertiary alcohols are not oxidized similarlySyllabus objective3.2.10Reduction of organic functional groups• Carboxylic acids → aldehydes → primary alcohols• Ketones → secondary alcohols• Include hydride ion role; specific reducing agents and mechanisms are not assessedSyllabus objective3.2.11Reduction of unsaturated compounds• Addition of H₂ lowers unsaturation• Alkenes + H₂, alkynes + H₂• Deduce hydrogenation products of alkenes and alkynesSyllabus objective3.2.12(HL)—Standard electrode potential (E⦵)• Hydrogen half-cell = 0 V by convention• Ease of oxidation/reduction• Use standard conditions and electrode potential data to compare oxidizing/reducing abilitySyllabus objective3.2.13(HL)—Standard cell potential (E⦵cell)• Calculate from E⦵ values• Positive E⦵cell = spontaneous• Predict feasible redox reactions from E⦵cellSyllabus objective3.2.14(HL)—Gibbs energy and cell potential• ΔG⦵ = −nFE⦵cell• Link electron number, Faraday constant, and spontaneitySyllabus objective3.2.15(HL)—Electrolysis of aqueous solutions• Competing reactions at electrodes• Water oxidation/reduction• Deduce products from standard electrode potentials; include water and aqueous solutionsSyllabus objective3.2.16(HL)—Electroplating• Electrolytic coating with metal layer• Explain the metal object as cathode and the coating metal as ion sourceSyllabus objective