UPSC Chemistry Syllabus 2021 for IAS Mains (Paper 1 & 2)
UPSC Chemistry Syllabus 2021 - The Union Public Service Commission (UPSC) mentions the UPSC 2021 Chemistry syllabus in the official notification and releases it on the official website. The syllabus of UPSC Chemistry 2021 is based on graduation level. The topics as per the UPSC Chemistry syllabus 2021 are on atomic structure, states of matter, chemical bonding, thermodynamics, reactions etc. Aspirants who are choosing Chemistry as their optional subject in their mains exam of UPSC CSE can check the UPSC 2021 Chemistry syllabus here. The detailed syllabus is mentioned paper-wise for both the papers of the mains exam of UPSC CSE 2021. Chemistry is one of the Optional Subjects with 2 papers (Optional Paper I and Paper II). Apart from the UPSC 2021 Chemistry syllabus, we will share the preparation strategy, tips, tricks as well as best books and the IAS exam pattern. Candidates must also check the overall syllabus of UPSC CSE. Check the details syllabus of UPSC Chemistry 2021 here.

UPSC Chemistry Syllabus 2021 - Paper 1
Aspirants picking Chemistry as their optional subject can check the topics and subtopics on which the UPSC Chemistry Syllabus 2021 will be based on.
1. Solid State: Bragg's law; Structures of NaCl, ZnS, CsCl, CaF2; Close packing, radius ratio rules, Crystal systems; Designation of crystal faces, lattice structures and unit cell; X-ray diffraction by crystals; Stoichiometric and nonstoichiometric defects, calculation of some limiting radius ratio values; semiconductors, impurity defects.
2. Chemical bonding: This section will have topics on characteristics of ionic compounds, lattice energy, Ionic bond, Born-Haber cycle; covalent bond and its general characteristics; polarities of bonds in molecules and their dipole moments, Valence bond theory, Molecular orbital theory (LCAO method); the concept of resonance and resonance energy; bonding H2 +, H2 He2 + to Ne2, NO, CO, HF, CN–, bond order, bond strength, Comparison of valence bond and molecular orbital theories, and bond length.
3. Liquid State: Kelvin equation; Surface tension and surface energy, Wetting and contact angle, capillary action and interfacial tension.
4. Atomic Structure: Heisenberg's uncertainty principle Schrodinger wave equation (time-independent); particle in one- dimensional box, Interpretation of wave function, quantum numbers, hydrogen atom wave functions; Shapes of s, p and d orbitals
5. Electrochemistry: electrochemical series, Galvanic cells, concentration cells; measurement of e.m.f. of cells and its applications fuel cells and batteries. Processes at electrodes; double layer at the interface; the rate of charge transfer, current density; overpotential; electroanalytical techniques: amperometry, ion-selective electrodes and their use. Debye-Huckel theory of strong electrolytes and Debye-Huckel limiting Law for various equilibrium and transport properties.
6. The Gaseous State and Transport Phenomenon: Equation of state for real gases, Intermolecular interactions, Intermolecular collisions, critical phenomena and liquefaction of gases; collisions on the wall and effusion; Maxwell’s distribution of speeds, Thermal conductivity and viscosity of ideal gases.
7. Thermodynamics: Second law of thermodynamics; entropy changes in various processes, entropy as a state function, entropy-reversibility and irreversibility, Thermodynamic equation of state; Maxwell relations; Free energy functions; Temperature, volume and pressure dependence of U, H, -T effect and inversion temperature; the relation between equilibrium constant and thermodynamic quantities; criteria for equilibrium, Nernst heat theorem, the introductory idea of the third law of thermodynamics. Work, heat and internal energy; first law of thermodynamics.
8. Phase Equilibria and Solutions: 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.
9. Bio-inorganic Chemistry: Metal ions in biological systems and their role in ion transport across the membranes (molecular mechanism), oxygen-uptake proteins, cytochromes and ferredoxins.
10. Chemical Kinetics: Study of fast reactions by stop-flow and relaxation methods. Collisions and transition state theories. Differential and integral rate equations for zeroth, first, second and fractional order reactions; Consecutive and chain reactions, Rate equations involving reverse, parallel; effect of temperature and pressure on rate constant, Branching chain and explosions;
11. Surface Phenomena and Catalysis: Absorption from gases and solutions on solid adsorbents; Langmuir and B.E.T. characteristics and mechanism of reaction on heterogeneous catalysts, adsorption isotherms; determination of surface area.
12. Coordination Chemistry :
(i) Valence bond theory, crystal field theory and its modifications; applications of theories in the explanation of magnetism and electronic spectra of metal complexes, Bonding in the transition of metal complexes.
(ii) Isomerism in coordination compounds; IUPAC nomenclature of coordination compounds; trans effect and its theories; stereochemistry of complexes with 4 and 6 coordination numbers; kinetics of substitution reactions in square-planar complexes; chelate effect and polynuclear complexes; thermodynamic and kinetic stability of complexes.
(iii) EAN rule, Synthesis structure and reactivity of metal carbonyls; carbonyl hydrides and metal nitrosyl compounds, carboxylate anions
(iv) Complexes with aromatic systems, synthesis, alkyne complexes and cyclopentadienyl complexes; structure and bonding in metal olefin complexes, oxidative addition reactions, insertion reactions, coordinative unsaturation, fluxional molecules and their characterization; Compounds with metal-metal bonds and metal atom clusters.
13. Photochemistry: Absorption of light; decay of excited state by different routes; photochemical reactions between hydrogen and halogens and their quantum yields.
14. Main Group Chemistry: Interhalogen compounds, Boranes, phosphazenes and cyclic phosphazene, borazines, silicates and silicones, Sulphur—nitrogen compounds, noble gas compounds.
15. General Chemistry of ‘f’ Block Element: Lanthanides and actinides: separation, oxidation states, magnetic and spectral properties; lanthanide contraction.
UPSC Chemistry Syllabus 2021 - Paper 2
As per the UPSC Chemistry 2021 Syllabus the paper 2 will be based on the topics and subtopics as mentioned below:
1. (i) Reaction mechanisms: General methods (both kinetic and non-kinetic) of study of mechanisms or organic reactions: isotopies, method crossover experiment, intermediate trapping, stereochemistry; the energy of activation; kinetic control of reactions and thermodynamic control
(ii) Reactive intermediates: Generation, stability and reactions of Carbenium ions and carbanions, geometry, carbenes, free radicals, benzynes and nitrenes.
(iii) Substitution reactions:—SN 1, SN 2, and SN i, mechanisms; neighbouring group participation; electrophilic and nucleophilic reactions of aromatic compounds including heterocyclic compounds—pyrrole, furan, thiophene and indole.
(iv) Elimination reactions:— E1, E2 and E1cb mechanisms; orientation in E2 reactions—Saytzeff and Hoffmann; Chugaev and Cope eliminations, pyrolytic syn elimination—acetate pyrolysis.
(v) Addition reactions:— ed olefins and carbonyls.
(vi) Reactions and Rearrangements :—(a) Beckmann, Hoffmann, Pinacol-pinacolone, Fries, Baeyer-Villiger, Claisen, Favorskii, Cope, Stevens and Wagner—Meerwein rearrangements.
(b) Aldol condensation, Perkin, Dieckmann, Knoevenagel, Clemmensen, Claisen condensation, Witting, Wolff-Kishner, Cannizzaro and von Richter reactions; Stobbe, benzoin and acyloin condensations; Skraup synthesis, Fischer indole synthesis, Reformatsky reactions and Sandmeyer and Bischler-Napieralski, Reimer-Tiemann.
2. Delocalised Covalent Bonding: Anti-aromaticity; azulenes, aromaticity, annulenes, tropolones, sydnones, fulvenes.
3. Pericyclic reactions:— Classification and examples; Woodward-Hoffmann
rules—electrocyclic reactions, cycloaddition reactions [2+2 and 4+2] and sigmatropic
shifts [1, 3; 3, 3 and 1, 5], FMO approach.
4. Synthetic Uses of Reagents: HlO4, CrO3, OsO4, Pb(OAc)4, NBS, SeO2, B2H6, Na-Liquid NH3, NaBH4, LiAIH4, n-BuLi, MCPBA.
5. Spectroscopy: Principle and applications in structure elucidation :
(i) Rotational—Diatomic molecules; rotational constants and isotopic substitution.
(ii) Vibrational—Diatomic molecules, specific frequencies of functional groups in polyatomic molecules and linear triatomic molecules.
(iii) Electronic—Singlet and triplet states. Conjugated double bonds and conjugated carbonyls Woodward-Fieser rules; Charge transfer spectra.
(iv) Nuclear Magnetic Resonance (1HNMR): Basic principle; coupling constants and chemical shift and spin-spin interaction.
(v) Mass Spectrometry:— McLafferty rearrangement, metastable peak, Parent peak, base peak.
6. (i) Preparation and Properties of Polymers: polyvinyl chloride, polystyrene, Organic polymers polyethene, synthetic, natural rubber, Teflon, nylon and terylene,
(ii) Biopolymers: Structure of proteins, RNA and DNA.
7. Photochemistry:— Photochemical reactions of simple organic compounds, excited and ground states, singlet and triplet states, Norrish-Type I and Type II reactions.
UPSC Chemistry Syllabus 2021 - Preparation Tips
Aspirants planning to appear for UPSC IAS, must do it in a better way especially considering the tight competitiveness. Here we are sharing some UPSC IAS preparation tips that will help candidates in handy and help candidates to score well and qualify them for the UPSC exam. Check the tips here.
Only refer to NCERT books to prepare for Chemistry.
Make a perfect IAS study plan and stick to it.
UPSC CSE Chemistry requires a high-level preparation level and the difficulty level is of graduation level, hence candidates must start the preparations early.
Solve previous year questions papers of Chemistry mains exam to know about the type of questions that are asked in the exam. Also, look for UPSC IAS question papers for Chemistry and solve mocks.
Do previous year UPSC IAS exam analysis, to know about difficulty level of the exam, question trends and also to work on your weaker subjects.
UPSC Chemistry Syllabus 2021 Best Books
From the following table, check the list of best books for UPSC IAS preparation.
Best books for Chemistry
Best books | Author |
NCERT books of Chemistry from 6-12 | NCERT |
A guide to mechanism in organic chemistry | Peter Sykes |
A textbook of environmental chemistry and pollution | S.S. Dara |
Organic Chemistry Reactions and reagents | O.P. Agarwal |
Principle of physical chemistry | Puri, Sharma & Pathway |
A textbook of organic chemistry | Bahl & Ba |
Advanced Inorganic Chemistry | J.D. Lee |
Extradition of metals, Principle of inorganic chemistry | Puri, Sharma, Jauhar |
A textbook of physical chemistry (Vol. – IV) | K.L. Kapoor |
Advance physical chemistry | Gurdeep Raj |
Also read
Frequently Asked Question (FAQs) - UPSC Chemistry Syllabus 2021 for IAS Mains (Paper 1 & 2)
Question: Is Chemistry a good subject to be taken as optional?
Answer:
Yes, but only if you have interest in Chemistry as a subject, or else it can be difficult.
Question: How to prepare for Chemistry?
Answer:
The difficulty level of Chemistry is of graduation level. Hence the preparation takes a lot of time, aspirants must refer to only the best books for preparation.
Question: Which is the easiest optional subject for UPSC CSE?
Answer:
There is no easy or difficult subject, it all depends on your interest and likeability as well as how you can prepare and qualify it. However, maximum candidates pick Sociology, Geography and Public Administration as their optional subjects.
Question: What degree is required to apply for UPSC?
Answer:
To apply for UPSC, aspirants must be a graduate.
Question: Who scored the highest marks in UPSC CSE ever?
Answer:
It was Anudeep Durishetty, she scored 1125 marks out of 2025 in UPSC CSE.