Class 12 Chemistry
Study Material
A focused Class 12 Chemistry learning resource covering Physical, Inorganic and Organic Chemistry with important formulae, concepts, reactions, revision points and examination practice.
Complete Unit Roadmap
The page follows the current CBSE Class 12 Chemistry theory structure for the 2026–27 academic session.
Solutions
Concentration terms, solubility, vapour pressure and colligative properties.
- Molarity, molality and mole fraction
- Raoult's law
- Colligative properties
- Abnormal molar masses
Electrochemistry
Electrochemical cells, conductance, Nernst equation and electrolysis.
- Galvanic and electrolytic cells
- EMF and cell potential
- Nernst equation
- Faraday's laws
Chemical Kinetics
Reaction rate, rate laws, integrated equations and activation energy.
- Rate of reaction
- Order and molecularity
- Half-life
- Arrhenius equation
d- and f-Block Elements
Transition elements, oxidation states, colours, magnetic properties and lanthanoids.
- General characteristics
- Important compounds
- Lanthanoid contraction
- Oxidation states
Coordination Compounds
Coordination entities, nomenclature, bonding, isomerism and applications.
- Coordination number
- IUPAC nomenclature
- VBT and CFT
- Isomerism
Haloalkanes & Haloarenes
Preparation, properties and important substitution and elimination reactions.
- C–X bond
- SN1 and SN2 concepts
- Elimination reactions
- Important reactions
Alcohols, Phenols & Ethers
Preparation, properties and reactions of important oxygen-containing compounds.
- Alcohol reactions
- Phenol acidity
- Ether preparation
- Named reactions
Aldehydes, Ketones & Carboxylic Acids
Carbonyl chemistry, preparation methods, reactions and important tests.
- Nucleophilic addition
- Aldol reaction
- Important tests
- Carboxylic acid reactions
Amines
Classification, nomenclature, preparation, basicity and important reactions.
- Primary, secondary and tertiary amines
- Basic strength
- Diazonium salts
- Important conversions
Biomolecules
Carbohydrates, proteins, enzymes, vitamins and nucleic acids.
- Glucose and fructose
- Amino acids and proteins
- Vitamins
- DNA and RNA
Solutions
Master concentration terms and colligative properties before attempting numerical questions.
Molarity
M = moles of solute / volume of solution in L
Molality
m = moles of solute / mass of solvent in kg
Mole Fraction
χA = nA / (nA + nB)
Raoult's Law
pA = χAp°A
Relative Lowering
(p° − p)/p° = χsolute
Elevation in Boiling Point
ΔTb = Kbm
Depression in Freezing Point
ΔTf = Kfm
Osmotic Pressure
π = CRT
Van't Hoff Factor
i = observed colligative property / calculated property
Exam Tip
Always check whether the question gives mass, volume, moles or number of particles. Convert to the required concentration term before substituting into a formula.
Electrochemistry
A high-value numerical chapter involving cell potential, conductance, Nernst equation and electrolysis.
Cell EMF
E°cell = E°cathode − E°anode
Gibbs Energy
ΔG° = −nFE°cell
Equilibrium Relation
ΔG° = −RT ln K
Nernst Equation
E = E° − (0.0591/n) log Q
Resistance
R = V/I
Conductance
G = 1/R
Conductivity
κ = G × cell constant
Molar Conductivity
Λm = κ × 1000 / C
Faraday's Law
m = ZIt
Oxidation
Occurs at the anode.
Reduction
Occurs at the cathode.
Galvanic Cell
Converts spontaneous chemical energy into electrical energy.
Chemical Kinetics
Understand rate laws, integrated equations, half-life and activation energy.
Average Rate
Rate = −Δ[R]/Δt
Rate Law
Rate = k[A]m[B]n
Order
Order = m + n
First Order
k = 2.303/t log(a/(a−x))
First Order Half-Life
t1/2 = 0.693/k
Arrhenius Equation
k = Ae−Ea/RT
Log Form
log k = log A − Ea/(2.303RT)
Two Temperatures
log(k₂/k₁) = Ea/2.303R × (T₂−T₁)/(T₁T₂)
Rate Constant
Units depend upon the overall order of reaction.
d- and f-Block Elements
Focus on trends, oxidation states, magnetic behaviour, colours, catalytic activity and important compounds.
Variable Oxidation States
Transition elements commonly show multiple oxidation states because of the close energies of ns and (n−1)d orbitals.
Colour
Many transition-metal ions are coloured because of electronic transitions involving d-orbitals.
Magnetic Behaviour
Unpaired electrons generally produce paramagnetism.
Catalytic Activity
Variable oxidation states and surface interactions make many transition metals effective catalysts.
Lanthanoid Contraction
Gradual decrease in atomic and ionic radii across the lanthanoid series.
Interstitial Compounds
Small atoms can occupy spaces within metal lattices, producing characteristic compounds.
Revision Focus
Revise electronic configurations, common oxidation states, important ions, magnetic behaviour, colour and the important reactions and compounds included in the syllabus.
Coordination Compounds
One of the most important conceptual chapters for understanding complex ions, nomenclature, bonding and isomerism.
Coordination Number
Number of donor atoms directly attached to the central metal.
Ligand
Ion or molecule capable of donating an electron pair to the central metal.
Oxidation State
Find the metal oxidation state from the overall charge and ligand charges.
Magnetic Moment
μ = √n(n+2) BM
Coordination Entity
Central metal atom/ion plus its attached ligands.
Chelation
Formation of a ring structure when a multidentate ligand coordinates to a metal.
Ionisation Isomerism
Different ions are present inside and outside the coordination sphere.
Linkage Isomerism
Ambidentate ligands coordinate through different donor atoms.
Geometrical Isomerism
Different spatial arrangements of ligands around the central metal.
VBT
Uses hybridisation to describe bonding and geometry.
CFT
Explains splitting of d-orbital energies in ligand fields.
Crystal Field Splitting
Difference in energy between split d-orbital sets.
Haloalkanes & Haloarenes
Understand substitution, elimination, reactivity and important conversions.
SN1 Reaction
Proceeds through a carbocation intermediate and generally follows first-order kinetics.
SN2 Reaction
One-step nucleophilic substitution involving backside attack.
Elimination
Removal of atoms/groups from adjacent carbons can produce an alkene.
Wurtz Reaction
Alkyl halides can couple in the presence of sodium under suitable conditions.
Finkelstein Reaction
Alkyl chlorides or bromides can be converted to alkyl iodides using suitable iodide conditions.
Swarts Reaction
Used for preparation of alkyl fluorides from suitable alkyl halides.
Organic Exam Tip
Always identify whether the substrate is primary, secondary or tertiary before deciding which substitution or elimination pathway is most likely.
Alcohols, Phenols & Ethers
Build a reaction map instead of memorising isolated equations.
Alcohol → Alkene
Dehydration of alcohol under suitable acidic conditions can form an alkene.
Alcohol → Aldehyde/Ketone
Oxidation of primary and secondary alcohols gives characteristic carbonyl products.
Williamson Ether Synthesis
Alkoxide ions react with suitable alkyl halides to form ethers.
Kolbe Reaction
Sodium phenoxide can undergo carboxylation to form salicylic acid after suitable work-up.
Reimer-Tiemann Reaction
Phenol can give an aldehyde product under suitable chloroform/alkali conditions.
Ether Cleavage
Ethers can be cleaved by strong hydrogen halides under appropriate conditions.
Phenol Acidity
Phenol is more acidic than ordinary alcohols because the phenoxide ion is resonance stabilised.
Lucas Test
Used to distinguish alcohol classes based on the relative rate of turbidity formation under the test conditions.
Boiling Point
Hydrogen bonding significantly influences the physical properties of alcohols.
Aldehydes, Ketones & Carboxylic Acids
A major organic unit involving carbonyl chemistry, tests, named reactions and conversions.
Nucleophilic Addition
Carbonyl carbon is electrophilic and can undergo addition with suitable nucleophiles.
Aldol Condensation
Aldehydes or ketones containing suitable α-hydrogen can undergo aldol-type reactions under appropriate conditions.
Cannizzaro Reaction
Aldehydes without suitable α-hydrogen can undergo disproportionation under strongly basic conditions.
Tollens' Test
Aldehydes generally reduce Tollens' reagent under the test conditions.
Fehling's Test
Many aliphatic aldehydes give a characteristic positive Fehling's test.
Decarboxylation
Suitable carboxylic acid derivatives can undergo decarboxylation under appropriate conditions.
Carbonyl Recognition
When you see C=O, identify whether it belongs to an aldehyde, ketone, carboxylic acid or derivative. The functional group determines the likely reaction pattern.
Amines
Focus on classification, basicity, preparation, reactions and diazonium chemistry.
Primary Amine
One carbon group is attached to nitrogen in the basic amine structure.
Secondary Amine
Two carbon groups are attached to nitrogen.
Tertiary Amine
Three carbon groups are attached to nitrogen.
Basicity
Basic strength depends on electron density at nitrogen and the surrounding molecular environment.
Diazonium Salts
Aromatic primary amines can form diazonium salts under suitable cold conditions.
Coupling Reactions
Diazonium salts can participate in coupling reactions to form azo compounds.
Hoffmann Bromamide Reaction
An amide can be converted into an amine with one fewer carbon under suitable conditions.
Carbylamine Reaction
Primary amines can give isocyanides under suitable conditions.
Diazotisation
Aromatic primary amines react with nitrous acid at low temperature to form diazonium salts.
Sandmeyer Reaction
Diazonium groups can be replaced by suitable groups using appropriate copper(I) salts.
Biomolecules
A conceptual and memory-based unit that can be scored well with systematic revision.
Carbohydrates
Polyhydroxy aldehydes or ketones and their derivatives. Glucose and fructose are important examples.
Monosaccharides
Simple sugars that cannot be hydrolysed into smaller carbohydrate units.
Disaccharides
Carbohydrates that yield two monosaccharide units on hydrolysis.
Proteins
Polymers of amino acids linked through peptide bonds.
Enzymes
Biological catalysts that accelerate biochemical reactions.
Nucleic Acids
DNA and RNA are nucleic acids involved in storage, transmission and expression of genetic information.
Vitamins
Organic compounds required in small quantities for normal physiological functions.
DNA
Deoxyribonucleic acid, the major hereditary material in most organisms.
RNA
Ribonucleic acid involved in several biological processes including protein synthesis.
Class 12 Chemistry Formula Sheet
Keep this section for rapid revision before tests and board examinations.
Molality
m = moles of solute / kg solvent
Elevation
ΔTb = Kbm
Depression
ΔTf = Kfm
Osmotic Pressure
π = CRT
Cell Potential
E°cell = E°cathode − E°anode
Gibbs Energy
ΔG° = −nFE°
Nernst Equation
E = E° − 0.0591/n log Q
Conductance
G = 1/R
First Order
k = 2.303/t log(a/(a−x))
Half-Life
t1/2 = 0.693/k
Arrhenius
k = Ae−Ea/RT
Magnetic Moment
μ = √n(n+2) BM
Rate Law
Rate = k[A]m[B]n
Faraday Law
m = ZIt
Molar Conductivity
Λm = κ × 1000/C
Raoult's Law
pA = χAp°A
Important Reaction Map
Use functional-group recognition to connect the major organic reactions.
| Starting Group | Important Transformation | Product / Concept |
|---|---|---|
| Haloalkane | Nucleophilic substitution | Alcohol / Amine / other substituted product |
| Alcohol | Oxidation | Aldehyde / Ketone / Acid |
| Alcohol | Dehydration | Alkene |
| Phenol | Kolbe reaction | Salicylic acid after work-up |
| Phenol | Reimer-Tiemann | Aromatic aldehyde product |
| Aldehyde | Oxidation | Carboxylic acid |
| Carbonyl compound | Aldol reaction | β-hydroxy carbonyl / condensation product |
| Primary amine | Diazotisation | Diazonium salt |
| Diazonium salt | Sandmeyer reaction | Substituted aromatic product |
Important Questions to Practise
Use these question types for concept checks, numerical practice and board preparation.
Calculate molality, mole fraction and colligative properties for a given solution.
Apply van't Hoff factor to association or dissociation problems.
Calculate EMF of an electrochemical cell using standard electrode potentials.
Apply the Nernst equation to calculate cell potential.
Calculate ΔG°, equilibrium constant or cell potential using electrochemical relations.
Solve conductivity and molar conductivity numerical problems.
Determine order and rate constant from experimental kinetic data.
Calculate half-life and activation energy using Arrhenius relations.
Explain variable oxidation states, colour and magnetic properties of transition elements.
Explain lanthanoid contraction and its consequences.
Write IUPAC names of coordination compounds and determine oxidation state and coordination number.
Identify geometrical, optical and linkage isomerism in coordination compounds.
Compare SN1 and SN2 mechanisms and explain factors affecting them.
Write important reactions of haloalkanes and haloarenes.
Explain acidity of phenol and important reactions of alcohols and phenols.
Write important conversions involving alcohols, phenols and ethers.
Distinguish aldehydes and ketones using suitable chemical tests.
Write important reactions of aldehydes, ketones and carboxylic acids.
Explain basicity of amines and reactions of diazonium salts.
Revise carbohydrates, proteins, enzymes, vitamins and nucleic acids through comparison tables.
Common Class 12 Chemistry Mistakes
Avoid these common errors while preparing for board examinations.
Confusing molarity and molality in solution numericals.
Using incorrect units while calculating osmotic pressure or colligative properties.
Interchanging anode and cathode while calculating electrochemical cell potential.
Forgetting the reaction quotient while applying the Nernst equation.
Using the wrong integrated rate equation for the reaction order.
Confusing order of reaction with stoichiometric coefficients.
Writing incorrect oxidation states in coordination compounds.
Ignoring ligand charge while calculating the metal oxidation state.
Confusing SN1 and SN2 mechanisms.
Memorising organic reactions without understanding the functional group involved.
Confusing aldehyde and ketone identification tests.
Not revising organic conversions as connected reaction chains.
Class 12 Chemistry Exam Strategy
A balanced approach to Physical, Inorganic and Organic Chemistry can make revision much more effective.
Physical Chemistry
Understand formulas, units and assumptions. Solve numerical questions regularly and maintain a separate formula sheet.
Inorganic Chemistry
Create comparison tables for trends, oxidation states, compounds, coordination chemistry and important properties.
Organic Chemistry
Prepare functional-group reaction maps, named reactions, tests, conversions and mechanisms systematically.
Answer Writing
Write balanced equations, conditions, units and required structures clearly. Avoid unnecessary explanations where a precise equation is required.
Timed Practice
Practise complete papers under examination conditions and analyse every incorrect or incomplete answer.
Final Revision
Revise formulas, reactions, named reactions, important exceptions and previously made mistakes during the final revision cycle.
4-Step Chemistry Revision Plan
Learn
Understand the concept and solve examples.
Practise
Solve NCERT and examination-style questions.
Revise
Repeat formulas, reactions and difficult concepts.
Test
Attempt timed tests and correct every mistake.
OMEGA EDUCARE Chemistry Rule
Physical: Formula + concept + numerical practice. Inorganic: Concept + trends + structured revision. Organic: Functional group + reaction pattern + conversion practice.
Master Class 12 Chemistry
Build strong concepts, practise important numerical problems, master organic reaction pathways and prepare systematically for your Class 12 Chemistry examination with OMEGA EDUCARE.