🧪 OPTIONAL — CHEMISTRY

Papers: VI & VII · 500 marks. GS overlap: LOW (some GS-III S&T, environment). Best for: chemistry graduates/postgraduates.

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PAPER I — PHYSICAL AND INORGANIC CHEMISTRY

Physical Chemistry

1. Atomic structure: quantum theory, Heisenberg's uncertainty principle, Schrödinger wave equation (time independent); interpretation of wave function, particle in one-dimensional box, quantum numbers, hydrogen atom wave functions; shapes of s, p and d orbitals.
2. Chemical bonding: ionic bond, characteristics of ionic compounds, lattice energy, Born-Haber cycle; covalent bond and its general characteristics, polarities of bonds in molecules and their dipole moments; valence bond theory, concept of resonance and resonance energy; molecular orbital theory (LCAO method); bonding in H₂⁺, H₂, He₂⁺ to Ne₂, NO, CO, HF, CN⁻, CN, BeH₂ and CO₂; comparison of valence bond and molecular orbital theories, bond order, bond strength and bond length.
3. Solid state: forms of solids, law of constancy of interfacial angles, crystal systems and crystal classes; designation of crystal faces, lattice structures and unit cell; laws of rational indices; Bragg's law; X-ray diffraction by crystals; close packing, radius ratio rules, calculation of density of unit cell, structures of NaCl, ZnS, CsCl and CaF₂; stoichiometric and nonstoichiometric defects, impurity defects, semi-conductors.
4. The gaseous state and transport phenomenon: equation of state for real gases, intermolecular interactions, critical phenomena and liquefaction of gases; Maxwell's distribution of speeds, intermolecular collisions, collisions on the wall and effusion; thermal conductivity and viscosity of ideal gases.
5. Liquid state: Kelvin equation, surface tension and surface energy, wetting and contact angle, interface and capillarity, viscosity of liquids.
6. Thermodynamics: work, heat and internal energy; first law of thermodynamics; second law of thermodynamics, entropy, free energy functions; Gibbs-Helmholtz equation; criteria for equilibrium, relation between equilibrium constant and thermodynamic quantities; Nernst heat theorem and third law of thermodynamics.
7. Phase equilibria and solutions: phase equilibria in pure substances; Clausius-Clapeyron equation; phase diagram for a pure substance; phase equilibria in binary systems, partially miscible liquids, upper and lower critical solution temperatures; partial molar quantities, their significance and determination; excess thermodynamic functions and their determination.
8. Electrochemistry: Debye-Huckel theory of strong electrolytes and Debye-Huckel limiting law; electrochemical cells and Nernst equation; electrode/cell potentials; concentration cells; polarography, ion selective electrodes; corrosion and its prevention.
9. Chemical kinetics: concentration dependence of rate of reaction, differential and integral rate equations for zeroth, first, second and fractional order reactions; rate equations involving reverse, parallel, consecutive and chain reactions; effect of temperature and pressure on rate constant; collision theory and transition state theory; ionic reactions, kinetic isotope effects, homogeneous catalysis and Michaelis-Menten kinetics.
10. Photochemistry: absorption of light; decay of excited state by different routes; photochemical reactions between hydrogen and halogens and their quantum yields.

Inorganic Chemistry

11. Chemical periodicity: s, p, d and f block elements, periodic table; atomic, ionic and covalent radii; ionisation potential, electron affinity and electronegativity; periodic and group-wise variation of above properties in respect of s- and p-block elements.
12. Chemistry of coordination compounds: IUPAC nomenclature of coordination compounds, isomerism in coordination compounds; stereochemistry of complexes with 4 and 6 coordination numbers; chelate effect and polynuclear complexes; trans effect and its theories; kinetics of substitution reactions in square-planar complexes; stability constants of coordination compounds; valence bond, crystal field and molecular orbital theories.
13. Acid base titrations, complexometric titrations, neutralisation curves, indicators; redox titrations.
14. Chemistry of anionic species: halides and hydrides; oxides and oxyacids of B, C, N, P, S, Cl.
15. Non-aqueous solvents: reactions in liquid NH₃ and SO₂.
16. Chemistry of d-block and f-block elements.

PAPER II — ORGANIC CHEMISTRY AND SPECTROSCOPY

1. Delocalised covalent bonding: aromaticity, anti-aromaticity; annulenes, azulenes, tropolones, fulvenes, sydnones.
2. Reaction mechanisms: general methods (both kinetic and non-kinetic) of study of mechanism of organic reactions — isotopic method, cross-over experiment, intermediate trapping, stereochemistry; energy of activation; thermodynamic control and kinetic control of reactions.
3. Reactive intermediates: generation, geometry, stability and reactions of carbonium and carbanium ions, carbanions, free radicals, carbenes, benzynes and nitrenes.
4. Substitution reactions: SN1, SN2 and SNi mechanisms; neighbouring group participation; electrophilic and nucleophilic reactions of aromatic compounds including heterocyclic compounds — pyrrole, furan, thiophene and indole.
5. Elimination reactions: E1, E2 and E1cb mechanisms; orientation in E2 reactions — Saytzeff and Hoffmann; pyrolytic syn elimination.
6. Addition reactions: electrophilic addition to C=C and C≡C; nucleophilic addition to C=O, C≡N, conjugated olefins and carbonyls.
7. Reactions and rearrangements: Pinacol-pinacolone, Hoffmann, Beckmann, Baeyer-Villiger, Favorskii, Fries, Claisen, Cope, Stevens and Wagner-Meerwein rearrangements. Aldol condensation, Claisen condensation, Dieckmann, Perkin, Knoevenagel, Wittig, Clemmensen, Wolff-Kishner, Cannizzaro and von Richter reactions; Stobbe, benzoin and acyloin condensations; Fischer indole synthesis, Skraup synthesis, Bischler-Napieralski, Sandmeyer, Reimer-Tiemann and Reformatsky reactions.
8. Pericyclic reactions: classification and examples; Woodward-Hoffmann rules — electrocyclic reactions, cycloaddition reactions and sigmatropic shifts.
9. Preparation and properties of polymers: organic polymers — polyethylene, polystyrene, polyvinyl chloride, teflon, nylon, terylene, synthetic and natural rubber; biopolymers — structure of proteins, DNA and RNA.
10. Synthetic uses of reagents: OsO₄, HIO₄, CrO₃, Pb(OAc)₄, SeO₂, NBS, B₂H₆, Na-liquid NH₃, LiAlH₄, NaBH₄, n-BuLi and MCPBA.
11. Photochemistry: photochemical reactions of simple organic compounds, excited and ground states, singlet and triplet states, Norrish-Type I and Type II reactions.
12. Spectroscopy: principle and applications in structure elucidation — (a) Rotational — diatomic molecules, isotopic substitution and rotational constants; (b) Vibrational — diatomic molecules, linear triatomic molecules, specific frequencies of functional groups in polyatomic molecules; (c) Electronic — singlet and triplet states, n→π and π→π transitions, application to conjugated double bonds and conjugated carbonyls — Woodward-Fieser rules; (d) Nuclear Magnetic Resonance — proton NMR, chemical shift, spin-spin coupling, coupling constant; (e) Mass Spectrometry — parent peak, base peak, metastable peak, McLafferty rearrangement.

BOOKLIST

STRATEGY

• Mechanisms must be drawn with arrows — organic chemistry marks come from correct electron-flow depiction, not description.
• Numericals in physical chemistry need daily practice.
• Named reactions are guaranteed marks — make a master list with mechanism, conditions and an example.
• Draw structures and diagrams liberally; chemistry answers are visual.
• Solve 15 years of PYQs — question types repeat.

Pros: objective; static syllabus; good for chemistry postgraduates. Cons: almost no GS overlap; drawing-intensive under time pressure; requires strong subject grounding.