ISC EXAM CLASS 12TH LATEST UPDATE

Finally, wait is over and The Council for the Indian School Certificate Examinations (CISCE) has officially released the date sheet for ISC (Class 12) board examinations for 2025. This year class 12th board exam will be started from 13 February 2025 and will last upto 05 April 2025, it will take around 52 days to complete the class 12th board exam. The first exam will be held on 13 February 2025 for Environmental Science subject and the last exam will be held on 05 April 2025 for Art subject. The Indian School Certificate Examination results will be declared in the month of May.

Official Syllabus

There will be two papers in the subject:

Paper I: Theory - 3 hours ... 70 marks

Paper II: Practical: 3 hours ... 15 marks

Project Work … 10 marks

Practical File … 5 marks

PAPER I (THEORY) - 70 Marks

There will be no overall choice in the paper. Candidates will be required to answer all questions. Internal choice will be available in two questions of 2 marks each, two questions of 3 marks each and all the three questions of 5 marks each

PAPER I –THEORY – 70 Marks

1. Solid State

Solids: Their classification Based on different binding forces such as:  ionic, covalent molecular; amorphous and crystalline solids (difference), metals. Type of unit cell in two-dimensional and three-dimensional lattices, number of atoms per unit cell (all types). Calculation of density of unit cell, packing in solids, packing efficiency, voids, point defects, electrical and magnetic properties.

Band theory of metals. Conductors, semiconductors (n and p-type) and insulators.

(i) Crystal line and amorphous solids.

(ii) Definition of crystal lattice, unit cell; types of unit cell (scc, fcc, bcc); calculation of the number of atoms per unit cell; relationship between radius, edge length and nearest neighbour distance. Calculation of density of unit cell, formula of the compound–numericals based on it; packing in 3–D, packing fraction in scc, fcc, bcc with derivation; voids–types, location, formation (derivation of radius of voids).

(iii) Characteristics of crystalline solids; ionic (NaCl), metallic (Cu), atomic (diamond and graphite).

(iv) Point defects: Stoichiometric, non stoichiometric and impurity defects (F-centres).

(v) Electrical Properties: Conductors, semiconductors (n & p types) and insulators. 

(vi) Magnetic Properties: diamagnetic, paramagnetic.

2. Solutions

Study of concentration of solutions of solids in liquids, liquid in liquid, solubility of gases in liquids, Colligative properties-Raoult's law of relative lowering of vapour pressure elevation of boiling point, depression of freezing point, osmotic pressure. Use of colligative properties in determining molecular masses of solutes.

Normality, molality, molarity, mole fraction, as measures of concentration. Definition of the above with examples. Simple problems based on the above.

(i) Solubility of gases in liquids–Henry’s Law, simple numericals based on the above.

(ii) Raoult’s Law for volatile solutes and non-volatile solutes, ideal solution, non-ideal solution. Azeotropic mixtures–definition, types.

(iii) Colligative properties–definition and examples, and its use in determination of molecular mass.

(a) Relative lowering of vapour pressure: Definition and mathematical

ISC EXAM CLASS 12TH LATEST UPDATE

Finally, wait is over and The Council for the Indian School Certificate Examinations (CISCE) has officially released the date sheet for ISC (Class 12) board examinations for 2025. This year class 12th board exam will be started from 13 February 2025 and will last upto 05 April 2025, it will take around 52 days to complete the class 12th board exam. The first exam will be held on 13 February 2025 for Environmental Science subject and the last exam will be held on 05 April 2025 for Art subject. The Indian School Certificate Examination results will be declared in the month of May.

Official Syllabus

There will be two papers in the subject:

Paper I: Theory - 3 hours ... 70 marks

Paper II: Practical: 3 hours ... 15 marks

Project Work … 10 marks

Practical File … 5 marks

PAPER I (THEORY) - 70 Marks

There will be no overall choice in the paper. Candidates will be required to answer all questions. Internal choice will be available in two questions of 2 marks each, two questions of 3 marks each and all the three questions of 5 marks each

PAPER I –THEORY – 70 Marks

1. Solid State

Solids: Their classification Based on different binding forces such as:  ionic, covalent molecular; amorphous and crystalline solids (difference), metals. Type of unit cell in two-dimensional and three-dimensional lattices, number of atoms per unit cell (all types). Calculation of density of unit cell, packing in solids, packing efficiency, voids, point defects, electrical and magnetic properties.

Band theory of metals. Conductors, semiconductors (n and p-type) and insulators.

(i) Crystal line and amorphous solids.

(ii) Definition of crystal lattice, unit cell; types of unit cell (scc, fcc, bcc); calculation of the number of atoms per unit cell; relationship between radius, edge length and nearest neighbour distance. Calculation of density of unit cell, formula of the compound–numericals based on it; packing in 3–D, packing fraction in scc, fcc, bcc with derivation; voids–types, location, formation (derivation of radius of voids).

(iii) Characteristics of crystalline solids; ionic (NaCl), metallic (Cu), atomic (diamond and graphite).

(iv) Point defects: Stoichiometric, non stoichiometric and impurity defects (F-centres).

(v) Electrical Properties: Conductors, semiconductors (n & p types) and insulators. 

(vi) Magnetic Properties: diamagnetic, paramagnetic.

2. Solutions

Study of concentration of solutions of solids in liquids, liquid in liquid, solubility of gases in liquids, Colligative properties-Raoult's law of relative lowering of vapour pressure elevation of boiling point, depression of freezing point, osmotic pressure. Use of colligative properties in determining molecular masses of solutes.

Normality, molality, molarity, mole fraction, as measures of concentration. Definition of the above with examples. Simple problems based on the above.

(i) Solubility of gases in liquids–Henry’s Law, simple numericals based on the above.

(ii) Raoult’s Law for volatile solutes and non-volatile solutes, ideal solution, non-ideal solution. Azeotropic mixtures–definition, types.

(iii) Colligative properties–definition and examples, and its use in determination of molecular mass.

(a) Relative lowering of vapour pressure: Definition and mathematical expression of Raoult’s Law. Determination of relative molecular mass by measurement of lowering of vapour pressure.

(b) Depression in freezing point: molal depression constant (cryoscopic constant) – definition and mathematical expression (derivation included).

(c) Elevation in boiling point method: molal elevation constant (ebullioscopic constant) definition and mathematical expression (derivation included).

(d) Osmotic pressure: definition and explanation. Natural and chemical semi-permeable membranes, reverse osmosis, isotonic, hypotonic and hypertonic solutions. Comparison between diffusion and osmosis. Application of osmotic pressure in the determination of relative molecular mass. van’t Hoff-Boyle’s Law, van’t Hoff–Charles’ Law, van’t Hoff Avogadro’s law.

3. Electrochemistry

Electrolytic and electrochemical cells. Redox reactions in electrochemical cells. Electromotive Force (emf) of a cell, standard electrode potential, Nernst equation and its application to chemical cells. Relation between Gibbs energy change and emf of a cell.

Conductance in electrolytic solutions, specific, equivalent and molar conductivity, variations of conductivity with concentration, Kohlrausch's Law of electrolysis and Faraday’s Laws of electrolysis.

(i) Electrochemical cells: introduction, redox reactions (principle of oxidation and reduction in a cell).

(ii) Galvanic cells-introduction; representation, principle–oxidation reduction. Mechanism of production of electric current in a galvanic cell.

(iii) Measurement of potential. Single electrode potentials.

Standard hydrogen electrode - definition, preparation, application and limitations.

Standard electrode potential (E^o) - Measurement of standard electrode potential of Zn⁺⁺/ Zn, Cu⁺⁺/ Cu, half cell (using standard hydrogen electrode). Cell notation – representation.

Factors affecting electrode potential with explanation-main emphasis on the temperature, concentration and nature of the electrode.

(iv) Electrochemical series. Its explanation on the basis of standard reduction potential. Prediction of the feasibility of a reaction.

 Prediction of spontaneity of a reaction based on the cell emf.

Numericals on standard electrode potential of half-cells, cell emf, relationship between free energy and equilibrium constant, standard electrode potential and free energy.

(vi) Comparison of metallic conductance and electrolytic conductance. Relationship between conductance and resistance. Specific resistance and specific conductance.

Cell constant: Calculation of cell constant. Meaning of equivalent conductance. Meaning of molar conductance. General relationship between specific conductance, molar conductance and equivalent conductance (units and graphs).

Units, numericals.

Molar conductance of a weak electrolyte at a given concentration and at infinite dilution. Kohlrausch’s Law–definition, applications and numericals.

(vii) Faraday’s laws of Electrolysis.

Faraday’s First Law of electrolysis. Statement, mathematical form, Simple problems.

Faraday’s Second Law of electrolysis: Statement, mathematical form. Simple problems.

Relation between Faraday,  Avogadro’s number and charge on an electron. F = N_Ae should be given (no details of Millikan’s experiment are required).

4. Chemical Kinetics

Meaning of Chemical Kinetics–slow and fast reactions. Rate of a reaction-average and instantaneous rate (graphical representation). Factors affecting rate of reaction: surface area, nature of reactants, concentration, temperature, catalyst and radiation. Order and molecularity of a reaction, rate law and specific rate constant. Integrated rate equations and half-life (only for zero and first order reactions), concept of collision theory (elementary idea, no mathematical treatment). Concept of threshold and activation energy, Arrhenious equation.

(i) Meaning of chemical kinetics, Scope and importance of Kinetics of the reaction, slow and fast reactions–explanation in terms of bonds.

(ii) Rate of Reaction: definition, representation of rate of reaction in terms of reactants and products, determination of rate of reactions graphically, instantaneous and average rate of reaction. Factors affecting rate of reaction.

(iii) Law of mass Action: statement and meaning of active mass. Explanation with an example–general reactions.

(iv) Effect of concentration of reactants on the rate of a reaction: Qualitative treatment, based on the law of mass action, statement of rate law, General rate equation–
Rate = k(concentration of the reactant)ⁿ, where k is rate constant and n is the order of the reaction, relationship between the rate of the reaction with rate constant with respect to various reactants.

(v) Order of a reaction: meaning, relation between order and stoichiometric coefficients in balanced equations, order as an experimental quantity, rate equation for zero order reaction and its unit, mathematical derivation of rate equation for first order reaction, characteristics of first order reaction–rate constant is independent of the initial concentration, units to be derived, definition of half-life period, derivation of expression of half-life period from first order rate equation.

Problems based on first order rate equation and half-life period.

(vi) Molecularity of the reaction: Meaning–physical picture, Relation between order, molecularity and the rate of a reaction, Differences between order and molecularity of a reaction.

(viii) Effect of temperature on the rate constant of a reaction: Arrhenius equation – K = Ae^-Ea/RT. Meaning of the symbols of Arrhenius equation, related graph, evaluation of Ea and A from the graph, meaning of slope of the graph, conversion from exponential to log form of the equation, relationship between the increase in temperature and the number of collisions. Numerical based on Arrhenius equation.

5. Surface Chemistry

Absorption and Adsorption-physisorption and chemisorption, factors affecting adsorption of gases on solids and liquids. Catalysis; homogenous and heterogenous, activity and selectivity.

Colloidal state distinction between true solutions, colloids and suspension; lyophilic, lyophobic multi-molecular, macromolecular and associated colloids; properties of colloids; Brownian movement, Tyndall effect, coagulation and electrophoresis. Emulsion - types of emulsions.

(i) Difference between absorption and adsorption: definition of physisorption and chemisorption and their differences.

(ii) Catalysis: definition, types of catalysts – positive and negative, homogeneous and heterogeneous catalyst based on the state of the reactant and the catalyst, Elementary treatment of intermediate compound formation theory with examples; adsorption theory, effect of catalyst on the rate of reaction – the change in the energy of activation in the activation energy curve. Characteristics of a catalyst; specificity, activity, surface area of a catalyst. Promoter and poison.

(iii) Colloidal State: Thomas Graham classified the substances as crystalloid and colloid, classification of substances on the basis of the particle size i.e. true solution, sol and suspension, colloidal system is heterogeneous. lyophilic and lyophobic colloid; classification of colloidal solutions as micro, macro and associated colloids.

Properties of colloidal solutions: Brownian movement, Tyndall effect, coagulation, electrophoresis (movement of dispersed phase), Protection of colloids, Gold number and Hardy-Schulze rule. Emulsions, surfactants, micelles (only definition and examples).

Application of colloids and emulsions in daily life.

6. General Principles and Processes of Isolation of Elements

Metals: metallurgy, ores, principles and methods of extraction - concentration, oxidation, reduction, electrolytic refining. Occurrence and principles of extraction of aluminium, copper, zinc, iron and silver.

Definition of minerals, ores and metallurgy; principle ores of aluminium, iron, copper, zinc and silver.

Methods of concentration of ores: hydraulic washing, magnetic separation, froth floatation method, leaching.

Extraction of metal from concentrated ore–calcination, roasting and thermal reduction.

Metallurgy of iron, copper, zinc and silver.

Refining of metals-distillation, liquation, electrolysis.

7. p - Block Elements

Group - 15 Elements

Position in the periodic table, occurrence, electronic configuration, oxidation states, trends in physical and chemical properties. Nitrogen: preparation properties and its uses; compounds of nitrogen: oxides of nitrogen. Ammonia and nitric acid–preparation and properties. Phosphorus-allotropic forms, compounds of phosphorus: preparation and properties of phosphine.

(i) General introduction, electronic configuration, occurrence, oxidation states. Trends in physical properties; chemical properties with hydrogen, oxygen and halogens.

(iii) Nitric Acid - Preparation and manufacture. Properties: reaction with copper (dilute and concentrated HNO₃), carbon and sulphur Uses.

Group - 16 Elements

Position in the periodic table, occurrence, electronic configuration, oxidation states, trends in physical and chemical properties. Ozone–methods of preparation. Compounds of sulphur: preparation, properties and uses of sulphur-dioxide (industrial process of manufacture).

(i) Electronic configuration, oxidation states, occurrence. Trends in physical properties; chemical properties with hydrogen, oxygen and halogens.

(ii) Ozone: manufacture by Siemen’sozoniser, thermal decomposition of ozone, its oxidising nature–reaction with lead sulphide, potassium iodide and mercury, its uses.

(iii) Sulphur dioxide: laboratory and industrial preparation from sulphites and sulphide ores, reaction of sulphur dioxide with NaOH, Cl₂, KMnO₄.

Group - 17 Elements

Position in the periodic table, occurrence, electronic configuration, oxidation states, trends in physical and chemical properties; Preparation, properties and uses of chlorine. Inter halogen compounds.

Group - 18 Elements

Position in the periodic table, occurrence, electronic configuration, trends in physical and chemical properties, inert nature, uses.

(ii) Formation of xenon compounds with fluorine and oxygen (equations only), hybridisation, shape and structure of compounds.

(iii) Uses of noble gases.

8. d and f Block Elements

Position in the periodic table, occurrence, electronic configuration and characteristics of transition metals, general trends in properties of the3d-series of transition metals-metallic character, ionisation enthalpy, oxidation states, ionic radii, colour of ions, catalytic property, magnetic properties, properties of K₂Cr₂O₇ and KMnO₄.

Lanthanoids and actinoids.

(i) d-Block: 3d, 4d and 5d series

Study in terms of metallic character, atomic and ionic radii, ionisation enthalpy, oxidisation states, variable valency, formation of coloured compounds, formation of complexes, alloy formation.

(ii) f-Block: 4f and 5f series

Electronic configuration, atomic and ionic radii, oxidisation states, formation of coloured compounds, formation of complexes. Lanthanoid contraction and its consequences. Chemical reactivity–with oxygen, hydrogen, halogen, sulphur, nitrogen, carbon and water.

Actinoids - Oxidation states and comparison with lanthanoids.

(iii) Potassium permanganate: Structure, shape; its oxidising nature in acidic, basic and neutral medium, use in redox titration.

Oxidising nature in acidic [FeSO₄,(COOH)₂. 2H₂O, KI], basic (KI)and neutral (H₂S) mediums to be done.

(iv) Potassium dichromate: Structure, shape;its use in titration. Oxidising nature in acidic, basic and neutral medium, use in redoxtitration.

9. Coordination Compounds

Concept of complexes, definition of ligands, coordination number, oxidation number. IUPAC nomenclature of mono-nuclear coordination compounds. Isomerism (structural and stereo). Bonding, Werner's theory, VBT. Colour, magnetic properties and shapes. Importance of coordination compounds (inqualitative analysis, extraction of metals and biological system).

(i) Definition of coordination compounds /complex compounds, differences with a double salt, study of ligands–mono-, bi-, tri-, tetra-, penta-, hexa-and polydentate, chelating ligands, definition of coordination number, its calculation for a complex coordination sphere, study of oxidation state of an element in a complex, its calculation, IUPAC rules of nomenclature of coordination compounds.

(ii) Isomerism – structural, stereotypes and examples.

(iii) Valence bond theory of coordination compounds – examples of formation of inner orbital and outer orbital complexes (high and low spin, octahedral, tetrahedral and square planar), prediction of magnetic character.

(iv) Importance and uses.

10. Haloalkanes and Haloarenes.

Haloalkanes: General formula, nomenclature and classification. Nature of C–X bond, physical and chemical properties, mechanism of substitution reactions, optical rotation.

Haloarenes: Basic idea, nature of C–X bond, substitution reactions (directive influence of halogen in monosubstituted compounds only).

Nature of C-X bond

Naming the halogen derivatives of alkanes by using common system and IUPAC system for mono, di and tri-halo derivatives.

Preparation of haloalkanes from:

- Alkane and halogen.
- Alkene and hydrogen halide.
- Alcohols with PX₃, PCl₅ and SOCl₂.
- Halide exchange method (Finkelstein andSwarts)
- Silver salt of fatty acids (Hunsdiecker).

Physical properties: State, melting point, boiling point and solubility.

Chemical properties: nucleophilic substitution reactions (S_N1, S_N2 mechanism in terms of primary, secondary and tertiary halides) Reaction with: sodium hydroxide, water, sodium iodide, ammonia, primary amine, secondary amine, potassium cyanide, silver cyanide, potassium nitrite, silver nitrite, silver salt of fatty acid and lithium-aluminium hydride.

Elimination reaction (Saytzeff’s rule) / Beta elimination.

Reaction with metals: sodium and magnesium (Wurtz’s reaction, Grignard’s reagent preparation).

Chloroform and iodoform: preparation and properties.

Preparation of haloarenes by Sandmeyer’s and Gattermann’s reaction, by electrophilic substitution.

Physical properties: State, melting point, boiling point and solubility.

Chemical properties:

- Electrophilic substitution (chlorination, nitration and sulphonation).
- Nucleophilic substitution (replacement of chlorine with-OH,-NH2).
- Reduction of benzene.
- Wurtz-Fittig reaction.
- Fittig reaction.
- Addition reaction with magnesium (formation of Grignard reagent).

11. Alcohols, Phenols and Ethers

Alcohols: Classification, general formula, structure and nomenclature. Methods of preparation, physical and chemical properties (of primary alcohols only), identification of primary, secondary and tertiary alcohols, uses with special reference to methanol and ethanol.

(i) Classification into monohydric, dihydric and polyhydric alcohols, general formulae, structure and nomenclature of alcohols. Difference between primary, secondary and tertiary alcohols in terms of structure, physical properties and chemical properties.

(ii) Methods of preparation:

- Hydration of Alkenes – direct hydration, indirect hydration, hydroboration oxidation.
- From Grignard’s reagent.
- Hydrolysis of alkyl halides.
- Reduction of carbonyl compounds.
- From primary amines.

Properties:

- Acidic nature of alcohols:
- Reaction with sodium.
- Esterification.
- Reaction with hydrogen halides.
- Reaction with PCl₃,PCl₅, and SOCl₂.

- Reaction with acid chlorides and acid anhydrides
- Oxidation.
- Dehydration.

Uses of alcohols.

(iii) Conversion of one alcohol into another.

(iv) Distinction between primary, secondary and tertiary alcohols by Lucas’ Test.

Phenols: Classification and nomenclature. Methods of preparation, physical and chemical properties, acidic nature of phenol, electrophilic substitution reactions, uses of phenols.

Preparation of phenol from diazonium salt, chlorobenzene (Dow’s process) and from benzene sulphonic acid.

Manufactured from Cumene.

Physical properties: State and solubility.

Chemical properties:

- Acidic character of phenol.
- Reaction with sodium hydroxide.
- Reaction with sodium.
- Reaction with zinc.
- Reaction with acetyl chloride and acetic anhydride.
- Reaction with phosphorus penta chloride.
- Bromination, nitration and sulphonation (Electrophilic substitution reactions).
- Kolbe’s reaction (formation of salicylic acid).
- Reimer–Tiemann reaction
- Test for phenol–FeCl₃ test, azo dye test.

Aliphatic Ethers: General formula, structure and nomenclature. Methods of preparation, physical and chemical properties, uses.

Ethers: structure of ethereal group.

Preparation from alcohol (Williamson’s synthesis).

Physical properties: state, miscibility.

Chemical properties:

- Reaction with chlorine.
- Oxidation (peroxide formation).
- Reaction with HI.
- Reaction with PCl₅.

12. Aldehydes, Ketones and Carboxylic Acids

Aldehydes and Ketones: Nomenclature, structure of methods of preparation of aldehydes and ketones, physical and chemical properties, mechanism of nucleophilic addition, reactivity of alpha hydrogen in aldehydes and uses.

Preparation:

• From alcohol.
• From alkenes (ozonolysis).
• From alkynes (hydration).
• From acid chlorides (Rosenmund’s reduction, reaction with dialkyl cadmium).
• From calcium salt of carboxylic acids.
• From nitriles (Stephen reaction, Grignard’s reagent).
• From esters.

Physical properties – State and boiling point.

Chemical properties:

• Nucleophilic addition reactions with mechanism (ammonia and its derivatives, HCN, NaHSO₃ and Grignard’s reagent).
• Oxidation reactions, iodoform reaction.
• Reduction: reduction to alcohol and alkanes (Clemmensen’s reduction, Wolff-Kishnerreduction, Red phosphorus and HI).
• Base catalysed reactions: Aldol condensation, cross Aldolcondensation, Cannizzaro’s reaction.

Tests: Difference between formaldehyde and acetaldehyde; aldehydes and ketones.

Uses of aldehydes and ketones.

Aromatic aldehyde (Benzaldehyde)
Lab preparation from toluene by oxidation with chromyl chloride.

Physical properties: State and stability.

Chemical properties:

• Oxidation and reduction.
• Nucleophilic addition reaction (hydrogen cyanide and sodium bisulphite).
• Reactions with ammonia and its derivatives (hydroxyl amine, hydrazine and phenyl hydrazine).

• Reaction with phosphorus pentachloride.
• Cannizzaro reaction.
• Benzoin condensation.
• Perkin’s reaction.
• Electrophilic substitution-halogenation, nitration and sulphonation.

Test: The distinction between aromatic and aliphatic aldehydes.

Uses of benzaldehyde.

Carboxylic Acids: Classification, general formula and structure of Carboxylic group. Nomenclature, acidic nature, methods of preparation, physical and chemical properties and uses.

Classification of mono and dicarboxylic acids with examples.

Preparation of aliphatic and aromatic carboxylic acid:

- From alcohols, aldehydes.
- From nitriles.
- From Grignard’s reagent.

Physical properties: state, boiling point and solubility.

Chemical properties:

- Acidic character:(aliphatic, aromatic carboxylic acids with the effect of substituents on the acidic character–to be dealt with in detail)
- Reaction with active metals, alkalies, carbonates and bicarbonates,
- Formation of acid derivatives.
- Decarboxylation(chemical and Kolbe’selectrolytic reaction).
- HVZ reactions.
- Substitution of benzene ring (meta directive effect of Carboxylic acid group) nitration and sulphonation.

Tests for acids: formic acid, acetic acid and benzoic acid.

Uses of formic acid, acetic acid and benzoic acid.

13. Organic compounds containing Nitrogen

Aliphatic Amines: General formula and, classification of amines. Structure of the amino group, nomenclature. Methods of preparation, physical and chemical properties, Uses, identification of primary, secondary and tertiary amines.

•Amines

Nomenclature, classification with examples, structure, general formula.

Methods of preparation:

- From alcohol.
- From alkyl halide.
- From cyanide.
- From amide (Hofmann’sdegradation).
- From nitro compounds.
- Gabriel phthalimide Synthesis.

Physical properties: comparison between primary, secondary and tertiary amines in terms of–state, solubility, boiling point (hydrogen bonding), comparison with alcohols.

Chemical properties:

- Basic character of amines–comparison between primary, secondary and tertiary alkyl amines/ ammonia/ aniline. Effect of substituents on the basic strength of aniline
- Alkylation and acylation with mechanism.
- Reaction with nitrous acid.
- Carbylamine reaction.

Distinction between primary, secondary and tertiary amines (Hinsberg’s Test).

Aniline

Preparation reduction of nitrobenzene.

Physical properties – State, solubility and boiling point.

Chemical properties:

- Reaction with HCl and H₂ SO₄.
- Acetylation, alkylation.
- Benzoylation.

- Carbylamine reaction.
- Diazotisation.
- Electrophilic substitution (bromination, nitration and sulphonation).

Tests for aniline.

Uses of aniline.

Diazonium salts: Preparation, chemical reactions and importance in synthetic organic chemistry.

Preparation from aniline;

Properties: Sandmeyer’s reaction, Gattermann reaction, replacement of diazo group by–H,-OH,-NO₂, coupling reaction with phenol and aniline.

14. Biomolecules

Carbohydrates – Definition, Classification (aldoses and ketoses), monosaccahrides (glucose and fructose), D-L configuration oligosaccharides (sucrose), polysaccharides (starch, cellulose); Importance of carbohydrates.

Carbohydrates: Definition, classification-mono (aldose, ketose), oligo (di, tri, tetra saccharides) and polysaccharides with examples: reducing sugars and non-reducing sugars –examples and uses.

Heating with HI, reaction with hydroxylamine, bromine water and nitric acid.

Test for glucose and fructose (bromine water test with equation).

Disaccharides – structure of sucrose (glycosidic linkage).

Polysaccharides – starch, cellulose, glycogen.

Proteins – Structural units of proteins. Basic idea of-aminoacids, peptide bond, polypeptides, proteins, denaturation of proteins. Enzymes, hormones - elementary idea only.

Proteins: Amino acids – general structure, classification and zwitter ion formation. Isoelectric point.

Classification of proteins on the basis of molecular shape; denaturation of proteins. (Definitions only. Details and diagrams are not required).

Nucleic Acids - DNA and RNA.

Nucleic acids: basic unit – purine and pyrimidine, DNA–structure (double helical), RNA (No chemical structure required). Differences between DNA and RNA.

15. Chemistry in Everyday life

Chemicals in medicines - Analgesics, ranquilizers antiseptics, disinfectants, antimicrobials, antifertility drugs, antibiotics, antacids, antihistamines. 

In Medicine: antipyretics, analgesics, tranquillisers, antiseptics, disinfectants, anti-microbials, anti-fertility drugs, antihistamines, antibiotics, antacids.

Definition, common examples, uses. 

Differences between antiseptics and disinfectants.

Structure not required.

Chemicals in food - Preservatives, artificial sweetening agents elementary idea of antioxidants.

Preservatives: role, example (Sodium benzoate). Artificial sweetening agents: role, examples (aspartame, saccharine, sucralose and alitame).

PAPER II PRACTICAL WORK – 15 Marks

Candidates are required to complete the following experiments:

1. Titrations

Oxidation - Reduction titrations: potassium manganate (VII) / ammonium iron (II) sulphate; potassium manganate (VII) / oxalic acid. The candidate may be required to determine the percentage purity of a compound and the number of molecules of water of crystallization in hydrated salts. In such experiments sufficient working details including recognition of the end point will be given.

Candidates will be required to calculate:

• Molarity
• Concentration in grams L^-1/ molecular mass

• Number of molecules of water of crystallisation/ percentage purity.
• Concordant reading is to be used for titre value. Concordant reading is two consecutive values which are exactly the same. Average will not be accepted as titre value.
• The table is to be completed in ink only. Pencil is not to be used.
• Overwritingwill not be accepted in the tabular column.

Observations:

• Pipette size (should be same for all the candidates at the centre).
• Titre value (concordant value).

2. Study of the rate of reaction

The candidates will be required, having been given full instructions, to carry out an experiment on the rate of reaction, e.g. reaction between sodium thiosulphate and hydrochloric acid (using different concentrations for either), magnesium and dil. sulphuric acid/ dil. hydrochloric acid (using different concentrations).

• Graph of volume vs. time and its interpretation.
• Relationship between concentration and rate, volume and rate and time and rate.

3. Identification of the following compounds and functional groups based on observations

• Alcoholic group-glycerol•Aldehyde group-formaldehyde•Ketonic group–acetone•Carboxylic group–benzoic acid•Amino group-aniline

* Please Note: Carbylamine and acrolein tests should not be performed.

The student should learn to differentiate between colours, solution, ring and precipitate.

4. Characteristic tests of carbohydrates and proteins

• Carbohydrates–glucose
• Proteins–powdered milk

Identification should be of ‘Carbohydrate’ and ‘Protein’ not of individual substances.

5. Qualitative analysis

Qualitative analysis: identification of single salt containing one anion and one cation:

Anions: CO₃^2-, NO_2-, S^2-, SO₃^2-, SO₄^2-, NO₃^-, CH₃COO^-, Cl^-, Br^-, I^-, C₂O₄^2-, PO₄^3-.

Cations: NH₄⁺, Pb²⁺, Cu²⁺, Al³⁺, Fe³⁺, Zn²⁺, Mn²⁺, Ni²⁺, Co²⁺, Ba²⁺, Sr²⁺, Ca²⁺, Mg²⁺.

NOTE:

Chromyl chloride test not to be performed. For wet test of anions, sodium carbonate extract must be used (except for carbonate).

(Insoluble salts such as lead sulphate, barium sulphate, calcium sulphate, strontium sulphate will not be given).

Anions:

Dilute acid group – CO₃^2-, NO₂^-, S^2-, SO₃^2-

Concentrated Acid Group – NO₃^-, Cl^-, Br^-, I^-, CH₃COO^-.

Special Group - SO₄^2-, PO₄^3-, C₂O₄^2-.

Cations:

Group Zero: NH₄⁺

Group I: Pb²⁺

Group II: Cu²⁺, Pb²⁺

Group III: Al³⁺, Fe³⁺

Group IV: Zn²⁺, Mn²⁺, Ni²⁺,Co²⁺

Group V: Ba²⁺, Sr²⁺, Ca²⁺

Group VI: Mg²⁺

NOTE:

• Formal analytical procedure is required for Qualitative Analysis.
• Specific solvent for O.S. to be used;
• Before adding Group III reagents to the filtrate of Group II, H₂S must be removed followed by boiling with conc. Nitric acid.
• The right order for buffer (NH₄Cl and NH₄OH) must be used.
• The flame test with the precipitate obtained in Group V for Ba²⁺, Sr²⁺, Ca²⁺ will also be accepted as a confirmatory test.

For wet test of anions, sodium carbonate extract must be used (except for carbonate).

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