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INDEX MODULE 1 (A2):PHYSICAL CHEMISTRY........... 6 TOPIC 1: THERMODYNAMICS...................... 8 1. Born-Haber cycles.......................................... 8 2. Gibbs free-energy change, G, and entropy change, S.................... 10 TOPIC 2: RATE EQUATIONS....................... 13 1. Rate equations........................................... 13 2. Determination of rate equation................................. 14 TOPIC 3: EQUILIBRIUM CONSTANT K P FOR HOMOGENEOUS SYSTEMS............... 18 1. Equilibrium constant K p for homogeneous systems...................... 18 TOPIC 4: ELECTRODE POTENTIALS AND ELECTROCHEMICAL CELLS............... 20 1 Electrode potentials and cells................................... 20 2. Commercial applications of electrochemical cells....................... 22 TOPIC 4: ACIDS AND BASES....................... 25 1. Bronsted Lowry acid base equilibria in aqueous solution.................. 25 2. Definition and determination of ph............................... 25 3. The ionic product of water.................................... 26 4. Weak acids and bases, Ka for weak acids............................ 26 5. ph curves, titrations and indicators............................... 27 6. Buffer action............................................ 28 MODULE 2 (A2): INORGANIC CHEMISTRY......... 29 TOPIC 1: PROPERTIES OF PERIOD 3 ELEMENTS AND THEIR OXIDES...................... 31 1. Properties of period 3 elements and their oxides....................... 31 TOPIC 2: TRANSITION METALS..................... 35 1. General properties of transition metals............................. 35 2. Substitution reactions....................................... 36 3
3. Shapes of complex ions...................................... 38 4. Formation of coloured ions.................................... 39 5. Variable oxidation states..................................... 40 6. Catalysts............................................... 42 TOPIC 3: REACTIONS OF IONS IN AQUEOUS SOLUTION...... 44 1. Reactions of ions in aqueous solution.............................. 44 MODULE 3 (A2): ORGANIC CHEMISTRY........... 46 TOPIC 1: OPTICAL ISOMERISM..................... 48 1. Optical activity............................................ 49 TOPIC 2: ALDEHYDES AND KETONES................. 51 1. Oxidation of aldehydes...................................... 51 2. Nucleophilic addition........................................ 51 3. Reduction of carbonyls by NaBH 4......................................................... 52 TOPIC 3: CARBOXYLIC ACIDS AND DERIVATIVES.......... 55 1. Structure of Carboxylic Acids and Esters............................ 55 2. Carboxylic acids and esters.................................... 55 3. The esterification reaction (production of esters)....................... 56 4. Hydrolysis of esters........................................ 56 5. Uses of glycerol........................................... 57 6. Acylation............................................... 58 7. Mechanism for Addition-Elimination Reactions........................ 59 8. Acid Anhydrides........................................... 60 TOPIC 4: AROMATIC CHEMISTRY................... 62 1. Bonding............................................... 62 2. Experimental evidence for the structure of benzene..................... 62 3. Naming arenes........................................... 63 4. Electrophilic substitution..................................... 64 5. Friedel-Crafts Acylation...................................... 65 TOPIC 5: AMINES............................. 68 1. Preparation............................................. 68 2. Base properties........................................... 69 3. Basic strength............................................ 70 4. Nucleophilic properties...................................... 70 4
TOPIC 6: POLYMERS........................... 73 1. Condensation polymers...................................... 73 TOPIC 7: AMINO ACIDS, PROTEINS AND DNA............ 76 1. Amino acids............................................. 76 2. Proteins............................................... 76 3. Enzymes............................................... 78 4. Action of anticancer drugs..................................... 80 TOPIC 8: ORGANIC SYNTHESIS..................... 82 1. Organic Synthesis.......................................... 82 TOPIC 9: NUCLEAR MAGNETIC RESONANCE SPECTROSCOPY... 85 1. 13 C NMR............................................... 85 2. 1 H NMR................................................ 86 3. Spin-spin coupling peak splitting............................... 88 TOPIC 10: CHROMATOGRAPHY.................... 91 1. Chromatography.......................................... 91 2. Thin-layer Chromatography (TLC)................................ 91 3. Column Chromatography (CC).................................. 92 5
MODULE 1 (A2) PHYSICAL CHEMISTRY
TOPIC 1 Thermodynamics
Thermodynamics 1 Born-Haber cycles The lattice enthalpy, Δ L H, is the enthalpy change when one mole of a solid ionic lattice forms from its gaseous ions under standard conditions Depends on strength of the forces acting on ions in a lattice Strength of forces depends on: Product of the charges on ions (larger charges = larger forces) Sum of the radii of the cation and the anion (larger radii = smaller forces) Extent of covalency (more covalent = larger Δ L H ) Lattice enthalpies can be found using Born-Haber cycles, These are special versions of Hess cycles You can find Δ L H if you know the other energy terms in the cycle: Enthalpy of formation, Δ f H : the enthalpy change when a mole of a compound is formed from its elements (First/Second) Ionisation energy, Δ I(1/2) H : the energy required to remove a mole of electrons from a mole of gaseous atoms Enthalpy of atomisation, Δ a H : energy required to turn a molecule of an element into atoms in the gas phase e.g. Cl 2 (g) 2Cl(g) Bond enthalpy: the average heat needed to break a mole of covalent bonds, measured in the gaseous state (First/Second) Electron affinity, Δ EA(1/2) H : The standard enthalpy change when a mole of gaseous atoms is converted to a mole of gaseous ions, each with a single negative charge If you need to construct the Born-Haber cycle, start with a line for the elements in their standard states then add each step one by one snaprevise.co.uk 8
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