Chemistry HSC Science (General) 12th Standard Board Exam Maharashtra State Board Syllabus 2025-26

• Crystalline solids
• Amorphous solids
• Isomorphism and polymorphism 

• Classification of crystalline solids

1. Molecular solids:
   a) Polar molecular solids
   b) Non-polar molecular solids
   c) Hydrogen-bonded molecular solids
2. Ionic Solids
3. Metallic solids
4. Covalent or Network Solids

• Structure and properties of diamond, graphite, and fullerene

• Crystal, lattice and basis
• Unit Cell
• Types of unit cell
• Crystal systems

• Number of particles in cubic unit cells
• Relationship between molar mass, density of the substance and unit cell edge length, is deduced in the following steps

• Close packed structures
• Coordination number in close packed structure
• Number of voids per atom in hcp and ccp

• Band theory
• Metals
• Insulators
• Semiconductors
• Extrinsic semiconductors and doping

• Diamagnetic solids
• Paramagnetic solids
• Ferromagnetism

• Classification of crystalline solids

1. Molecular solids:
   a) Polar molecular solids
   b) Non-polar molecular solids
   c) Hydrogen-bonded molecular solids
2. Ionic Solids
3. Metallic solids
4. Covalent or Network Solids

• Structure and properties of diamond, graphite, and fullerene

• Classification of solids

1. Crystalline solids
2. Amorphous solids

• The distinction between Crystalline and Amorphous Solids
• Isomorphous solids and polymorphous solids

• Unit cell
• Crystal lattice or space lattice
• Two-dimensional lattice and unit cell
• Three-dimensional lattice and unit cell

• Calculation of density of unit cell

• Packing in solids
• Close Packing in One Dimension
  1) Coordination number
• Close Packing in Two Dimensions
  1) Square close packing in two dimensions
  2) Hexagonal close packing of spheres in two dimensions
• Close Packing in Three Dimensions
• Three-dimensional close-packed structure

• Stage I - Linear packing in one dimension
• Stage II - Planar packing in two dimensions
  1) AAAA type, square close-packed structure
  2) ABAB type, hexagonal close-packed structure
• Stage III - Close packing in three dimensions
  1) AAAA type, simple cubic structure
  2) ABAB type, hexagonal close-packed structure
  3) ABCABC type, cubic close-packed structure

• Number of voids per atom in hcp and ccp structures
• Locating tetrahedral and octahedral voids: locating tetrahedral voids, Locating octahedral voids

• Primitive Cubic Unit Cell
• Body-Centred Cubic Unit Cell
• Face-Centred Cubic Unit Cell

point defects and line defects

• Magnetic properties:

1. Magnetising field
2. Magnetic permeability
3. Intensity of magnetisation
4. Magnetic induction or total magnetic field
5. Magnetic susceptibility

• Substances can be classified into five categories:

1. Paramagnetic
2. Diamagnetic
3. Ferromagnetic
4. Antiferromagnetic
5. Ferrimagnetic

• Introduction

1. Gaseous Solutions
2. Liquid Solutions
3. Solid Solutions

• Factors affecting solubility

1. Nature of solute and solvent
2. Effect of temperature on solubility
3. Effect of pressure on solubility

• Raoult’s law
• Ideal and nonideal solutions

• Raoult’s law for solutions of nonvolatile solutes
• Relative lowering of vapour pressure
• Molar mass of solute from vapour pressure lowering

•  van’t Hoff factor(i)
• Modification of expressions of colligative properties
• van’t Hoff factor and degree of dissociation

1. Gaseous Solutions
2. Liquid Solutions
3. Solid Solutions

• Mass percentage (w/w)
• Volume percentage (V/V)
• Mass by volume percentage (w/V)
• Parts per million
• Mole fraction
• Molarity
• Molality
• Standard solutions and working standards
• Advantages of using standard solutions

• Abnormal molecular masses
  a) Association of solute particles
  b) Dissociation of solute particles
• Van't Hoff Factor
• Significance of van't Hoff factor
  a) Degree of dissociation
  b) Degree of association

• Strong electrolyte
• Weak electrolyte
• Degree of dissociation (∝)

• Arrhenius theory of acids and bases
• Bronsted - Lowry theory 
• Lewis theory

• Dissociation constant of weak acids and weak bases
• Ostwald's dilution law

• pH of a solution
• pH scale
• Relationship between pH and pOH
• Approximate pH values of some substances
• Acidity, basicity, and neutrality of aqueous solutions
• pK value
• Measurement of pH of a solution
• Indicators
• Titration curves

• Salts of strong acids and strong bases
• Salts of strong acids and weak bases
• Salts of weak acids and strong bases
• Salts of weak acids and weak bases

• Types of buffer solutions
• Buffer action
• Buffer capacity and buffer index
• Henderson - Hasselbalch equation
• Properties of buffer solution
• Applications of buffer solution

1. In biochemical system
2. Agriculture
3. Industry
4. Medicine
5. Analytical chemistry

Common ion effect and solubility

• System and surrounding
• Types of system
• Properties of system
• State functions
• Path Functions
• Thermodynamic equilibrium
• Process and its types

• Nature of work (W)
• Nature of heat (Q)
• Sign conventions of W and Q

• Free expansion
• Units of energy and work

Expression for the maximum work

• First law of thermodynamics
• Formulation of first law of thermodynamics
• First law of thermodynamics for various processes

1. Isothermal process
2. Adiabatic process
3. Isochoric process
4. Isobaric process

• Justification
• Mathematical expression
• Some useful conclusions are drawn from the law
• Limitations
• Expressions for the work done by an ideal gas under different conditions

• Enthalpy
• Relationship between ∆H and ∆U for chemical reactions
• Work done in chemical reaction

• Enthalpy of phase transition
• Enthalpy for the atomic / molecular change

• Enthalpy of chemical reaction (∆_rH)
• Exothermic and endothermic reactions
•  Standard enthalpy of reaction(∆_rH⁰)
• Thermochemical equation 
• Standard enthalpy of formation (∆_fH⁰)
• Standard enthalpy of reaction from standard enthalpies of formation
• Standard enthalpy of combustion (∆_cH⁰)
• Bond enthalpy
• Hess’s law of constant heat summation

• Energy and spontaneity
• Entropy
• Entropy and spontaneity (Second law of Thermodynamics)
•  Second law of thermodynamics
• Gibbs energy
• Gibbs energy and spontaneity
• Sponaneity and ∆H or ∆S
• Temperature of equilibrium
• Gibbs function and equilibrium constant

• Electrochemical reactions
• Electrodes
• Types of electrochemical cells

1. Galvanic cell
2. Electrolytic cells

• Conductors
• Difference between Electronic and Electrolytic conduction
• Non-electrolytes
• Factors affecting electronic or metallic conduction
• Factors affecting electrical conductivity of electrolytic solutions
• Electrolytic conduction (Conductance in electrolytic solutions)

• Electrolytic cells
• Process of electrolysis
• Preferential Discharge Theory
• Some Examples of Electrolysis
• Quantitative Aspects of Electrolysis
• Faraday's laws of electrolysis
  1) Faraday's First Law of Electrolysis
  2) Faraday's Second Law of Electrolysis

• Galvanic or Voltaic cells

• Reduction half-cell
• Oxidation half-cell
• Joining half-cells
• Anodic oxidation
• Cathodic reduction
• Completion of circuit
• Consumption of Electrodes

• Salt bridge
• Cell notation or representation of a galvanic cell
• Cell electromotive force (e.m.f.)

• Derivation of Nernst equation
• Applications of Nernst equation

• Gibbs energy change and e.m.f. of a cell
• Standard cell potential and equilibrium constant

• Redox reactions
• Half reactions

• Metallic conduction
• Electrolytic or ionic conduction
• Information provided by measurement of conductivities of solutions

•  Conductivity (k)
• Molar conductivity (∧)
• Relation between k and ∧
• Variation of conductivity with concentration
•  Variation of molar conductivity with concentration
• Variation of molar conductivity with concentration
• Kohlrausch law of independent migration of ions
• Molar conductivity and degree of dissociation of weak electrolytes
• Measurement of conductivity

• Electrochemical reactions
• Electrodes
• Types of electrochemical cells

1. Galvanic cell
2. Electrolytic cells

• Electrolysis of molten NaCl
• Electrolysis of aqueous NaCl
• Quantitative aspects of electrolysis

• Salt bridge
• Formulation or short notation of galvanic cells
• Writing of cell reaction

• Electrode potential
• Cell potential or e.m.f.
• Difference between e.m.f. and potential difference
• Standard electrode potential
• Dependence of cell potential on concentration (Nernst equation)

• Gibbs energy of cell reactions and cell potential
•  Standard cell potential and equilibrium constant

•  Standard hydrogen electrode (SHE)

• Dry cell (Leclanche' cell)
• Lead storage battery (Lead accumulator)
• Nickel-Cadmium or NICAD storage cell
• Mercury battery

• Fuel cells
• Hydrogen-oxygen fuel cell
• Advantage and disadvantage of fuel cell

• Electrochemical series
• Convention used in the construction of electrochemical series
• Applications of electrochemical series

• Various factors influencing the rate of a chemical reaction

1. Concentration of reactants
2. Pressure of gaseous reactants
3. Temperature of the system
4. Presence of a catalyst

• Dependence of Rate on Concentration, temperature, catalyst
• Rate Expression and Rate Constant/ Rate law and Specific Rate Constant
• Order of a Reaction
• Molecularity of a Reaction

• Half life of the first order reactions (`t _(1/2)`)
• Half life and rate constant of the first order reaction
• Graphical representation of Half life period of first order reaction
• Half life of zero order reactions

• Collision between reactant molecules
• Energy requirement - Activation energy
• Orientation of reactant molecules

• Activation energy
• Arrhenius equation
• Most probable kinetic energy
• Effect of Catalyst

• Average rate of chemical reaction
• Instantaneous rate

• Rate law
• Writing the rate law
• Order of the reaction

• Elementary reaction
• Complex reactions
• Molecularity of reaction
• Order and molecularity of elementary reactions
• Rate determining step
• Reaction intermediate
• Differences between order and molecularity

• Integrated rate law for first order reactions
• Units of rate constant for the first order reaction
• Graphical representation of first order reaction
• Examples of first order reactions
• Various forms of the integrated rate law for the first order reactions

• Integrated rate law for zero order reactions
• Units of rate constant of zero order reactions
• Graphical representation of zero order reaction
• Examples of zero order reactions

• Half life of the first order reactions (`t _(1/2)`)
• Half life and rate constant of the first order reaction
• Graphical representation of Half life period of first order reaction
• Half life of zero order reactions

• Collision between reactant molecules
• Activation
• Orientation of reactant molecules
• Potential energy barrier

• Arrhenius equation
• Graphical determination of activation energy
• Determination of activation energy
• Graphical description of effect of temperature

• Principles and methods of extraction - Refining

1. Distillation
2. Liquation 
3. Electrolytic refining (electrolytic method)
4. Zone refining
5. Vapour phase refining
6. Chromatographic methods

• Occurrence of metals
• Minerals and ores

• Ellingham diagrams
• Significance of Ellingham diagram
• Limitations of Ellingham diagram
• Selection of reducing agent

• Aluminium - Hall-Heroult process
• Copper from Low Grade Ores and Scraps

• Atomic properties of Group 16, 17 and 18 elements
• Physical properties of group 16, 17 and 18 elements

• Oxidation state
• Chemical Reactivity towards hydrogen
• Reactivity towards oxygen
• Reactivity towards halogens
• Reactivity towards metals

• Oxoacids of sulfur
• Oxoacids of halogens

• Dioxygen
• Simple Oxides
• Ozone

• Electronic configuration of chromium and copper

• Atomic and ionic radii 
• Ionisation Enthalpy
• Metallic character
• Magnetic Properties
• Colour
• Catalytic Properties
• Formation of interstitial compounds
• Formation of Alloys

• Metallurgy
• Extraction of Iron from Haematite ore using Blast furnace

• Electronic configuration
• Oxidation state
• Colour and Spectra
• Atomic and ionic radii (Lanthanoid Contraction)

Coordination entity, Central atom/ion, Ligands, Colour, Shapes, Coordination number, Coordination sphere, Coordination polyhedron, Oxidation number of central atom, Homoleptic and heteroleptic complexes, charge number

• Limitations of Werner’s theory

• Monodentate ligands
• Polydentate ligands
• Ambidentate ligand

• Coordination sphere
• Charge number of complex ion and oxidation state of metal ion
• Coordination number (C.N.) of central metal ion
• Double salt and coordination complex
• Werner theory of coordination complexes

• Classification on the basis of types of ligands
• Classification on the basis of charge on the complex

• Stereoisomers
• Structural isomers (Constitutional isomers)
• Optical Isomerism

• Factors which govern the stability of the complex

• Valence bond theory (VBT)
• Octahedral, complexes
• Tetrahedral complex
• Square planar complex
•  Limitations of VBT
• Crystal Field theory (CFT)
• Factors affecting Crystal Field Splitting parameter (∆₀)
• Colour of the octahedral complexes
• Tetrahedral complexes

• Classification of monohalogen compounds

•  From alcohol
• From hydrocarbon
• Halogen exchange
• Electrophilic substitution
• Sandmeyer's reaction

• Nature of intermolecular forces
• Boiling point
• Solubility

• Chiral atom and molecular chirality
• Plane polarized light
• Optical activity
• Enantiomers
• Representation of configuration of molecules

• Laboratory test of haloalkanes
• Nucleophilic substitution reactions of haloalkanes
• Mechanism of S_N reaction
• Factors influencing S_N1 and S_N2 mechanism
• Elimination reaction : Dehydrohalogenation

• Reaction of haloarenes

• Dichloromethane/methylene chloride (CH₂Cl₂)
• Chloroform/trichloromethane (CHCl₃)
• Carbon tetrachloride/tetrachloromethane (CCl₄)
• Idoform or triiodomethane (CHI₃)
• Freons
• Dichlorodiphenyltrichloroethane (DDT)

• Alcohols - Mono, di, tri and polyhydric compounds
• Phenols - Mono, Di and trihydric phenols
• Ethers - simple or symmetrical, mixed or unsymmetrical

• Nomenclature of aldehydes and carboxylic acid
• Trivial and IUPAC names of ketones

1. By oxidation of alcohols
2. By dehydrogenation of alcohols
3. From hydrocarbons
   (i) By ozonolysis of alkenes
   (ii) By hydration of alkynes

• From nitriles and amides
• From acyl chloride and anhydrides
• From esters
• From alkyl benzene
• From alkenes
• From Grignard reagent

• Nature of intermolecular forces
• Physical state and boiling points of aldehydes and ketones
• Solubility of aldehydes and ketones
• Physical state, boiling points and solubilities of carboxylic acids

• Reactivity of aldehydes and ketones

• Laboratory tests for aldehydes and ketones
• Chemical reactions of aldehydes and ketones with nucleophile
• Oxidation and reduction reactions of aldehydes and ketones
• Electrophilic substitution reactions

• Acidic character of carboxylic acids
• Laboratory tests for carboxyl (-COOH) group
• Formation of acyl chloride
• Reaction with ammonia
• Formation of acid anhydride
• Decarboxylation of carboxylic acids
• Reduction of carboxylic acids

• Classification of amines

1. Aliphatic amines
2. Aromatic amines

• Common names
• IUPAC names

• Basic strength of aliphatic amines
• Basicity of arylamines

• Reactions involving displacement of diazo group
• Reactions involving retention of diazo group: (Coupling reactions)

• Classification of polymers on the basis of source or origin
• Classification of polymers on the basis of structure
• Classification of polymers on the basis of mode of polymerization
• Classification of polymers on the basis of intermolecular forces
• Classification of polymers on the basis of type of different monomers
• Classification of polymers on the basis of biodegradability

• Poly β-hydroxybutyrate – co-β-hydroxy valerate (PHBV)
• Nylon 2– nylon 6
• Biodegradable and non-biodegradable polymers

• Mechanism of Addition Polymerisation
  1) Free radical mechanism
• Some Important Addition Polymers
  (a) Polythene
  (i) Low density polythene
  (ii) High density polythene
  (b) Polytetrafluoroethene (Teflon)
  (c) Polyacrylonitrile

• Condensation Polymerisation or Step Growth Polymerisation
• Some Important Condensation Polymers
  (a) Polyamides: Nylons
  (i) Nylon 6, 6
  (ii) Nylon 6
  (b) Polyesters
  (c) Phenol - formaldehyde polymer (Bakelite and related polymers)
  (d) Melamine - formaldehyde polymer

• Natural rubber (Vulcanisation of rubber),
• Synthetic rubbers

1. Buna-S rubber
2. Buna-N rubber or nitrile rubber
3. Neoprene rubber

• Poly β-hydroxybutyrate – co-β-hydroxy valerate (PHBV)
• Nylon 2– nylon 6
• Biodegradable and non-biodegradable polymers

• Case Study - Indira Gandhi Canal (Nahar) Command Area
• Measures for Promotion of Sustainable
  Development

• Prevention of waste or by products
• Atom economy
• Less hazardous chemical synthesis
• Desigining Safer Chemicals
• Use Safer solvent and auxilaries
• Design for energy efficiency
• Use of renewable feedstocks
• Reduce derivatives : [Minimization of steps]
• Use of catalysis
• Design for degradation
• Real-time Analysis Pollution Prevention
• Safer chemistry for Accident prevention

• Colour
• Surface area
• Catalytic activity
• Mechanical properties
• Electrical conductivity

• Wet chemical synthesis of Nanomaterials
• Analysis or characterization of nanomaterials
• Photographs of instruments