Grade 12
  1. Solid state  1.1. Classification of solids  1.2. Crystal Lattice and Unit Cell  1.3. Packing Efficiency  1.4. Density of unit cell  1.5. Imperfections in solids (point and line defects)  1.6. Electrical Properties of Solids (Conductors, Insulators and Semiconductors)  1.7. Magnetic Properties of Solids (Diamagnetic, Paramagnetic and Ferromagnetic Materials)
  2. Solution  2.1. Types of Solutions (Homogeneous and Heterogeneous)  2.2. Expressing concentration of solutions (mass %, volume %, molarity, molality, normality, mole fraction)  2.3. Solubility of solids and gases in liquids (Henry's law)  2.4. Raoult's Law and Ideal and Non-Ideal Solutions  2.5. Syndrome properties  2.6. Abnormal molar mass and Van't Hoff factor
  3. Electrochemistry  3.1. Electrochemical cells (galvanic and electrolytic cells)  3.2. Galvanic cell and EMF of the cell  3.3. Standard electrode potential and electrochemical series  3.4. Nernst equation and its applications  3.5. Conductivity and electrolytic cells (specific, molar and equivalent conductivity)  3.6. Kohlrausch's law and its applications  3.7. Batteries (primary and secondary cells)  3.8. Corrosion and its prevention
  4. Chemical kinetics  4.1. Rate of chemical reaction  4.2. Factors affecting the reaction rate (concentration, temperature, catalyst, surface area)  4.3. Order and molecularity of the reaction  4.4. Integrated Rate Equations (Zero, First and Second Order)  4.5. Half-life of a reaction  4.6. Collision theory and activation energy  4.7. Arrhenius equation and its applications
  5. Surface chemistry  5.1. Adsorption and its types (Physicosorption and Chemisorption)  5.2. Catalysis and its types (homogeneous and heterogeneous)  5.3. Colloids and their properties (Tyndall effect, Brownian motion, coagulation)  5.4. Emulsions and gels  5.5. Applications of Colloids
  6. General principles and processes of separation of elements  6.1. Presence of metals and minerals  6.2. Concentration of ores (gravity separation, froth flotation, magnetic separation)  6.3. Extraction of raw metals (roasting, calcination, reduction)  6.4. Thermodynamic and electrochemical principles of metallurgy  6.5. Refining of metals
  7. P-block elements  7.1. Group 15 elements (nitrogen and phosphorus)  7.2. Group 16 Elements (Oxygen, Sulphur and their Compounds)  7.3. Group 17 Elements (Halogens and their Compounds)  7.4. Group 18 Elements  7.5. Properties and Trends in p-Block Elements  7.6. Important compounds of p-block elements (ammonia, phosphine, sulphuric acid, hydrochloric acid)  7.7. Interhalogen compounds and their applications
  8. d-block and f-block elements  8.1. General Properties of Transition Metals  8.2. Properties of Inner Transition Metals (Lanthanoids and Actinoids)  8.3. Lanthanoid and actinoid contractions  8.4. Coordination Chemistry of d-Block Elements
  9. Coordination compounds  9.1. Werner's theory and modern concepts  9.2. Coordination number and type of ligand  9.3. Nomenclature of Coordination Compounds  9.4. Isomerism (geometrical and optical) in coordination compounds  9.5. Bonding in Coordination Compounds (Valence Bond Theory and Crystal Field Theory)  9.6. Stability and applications of coordination compounds in medicine and industry
  10. Haloalkanes and haloarenes  10.1. Classification and nomenclature of haloalkanes and haloarenes  10.2. Physical and Chemical Properties of Haloalkanes and Haloarenes  10.3. Mechanism of Nucleophilic Substitution Reactions (SN1 and SN2)  10.4. Uses and environmental effects (ozone depletion, CFCs)
  11. Alcohol, phenol and ether  11.1. Structure and classification of alcohols, phenols and ethers  11.2. Preparation and properties of alcohols  11.3. Preparation and properties of phenol  11.4. Preparation and properties of ethers  11.5. Chemical Reactions and Uses
  12. Aldehydes, ketones and carboxylic acids  12.1. Structure and nomenclature in aldehydes, ketones and carboxylic acids  12.2. Preparation and properties of aldehydes and ketones  12.3. Chemical reactions in aldehydes, ketones and carboxylic acids (nucleophilic addition, oxidation and reduction)  12.4. Preparation and Properties of Carboxylic Acids  12.5. Chemical Reactions and Uses of Carboxylic Acids
  13. Nitrogen-containing organic compounds  13.1. Amines (classification, structure, basicity)  13.2. Preparation and properties of amines  13.3. Reactions of Amines (Diazotization, Carbylamine Reaction)  13.4. Diazonium salts and their applications in paint industry
  14.1. Carbohydrates (classification and properties)  14.2. Proteins (Structure and Function)  14.3. Enzymes (Mechanism and Function)  14.4. Nucleic acids (DNA and RNA)  14.5. Vitamins and hormones
  15. Polymer  15.1. Classification of Polymers (Addition, Condensation, Copolymers)  15.2. Types of polymerization (free radical, ionic, condensation)  15.3. Important Polymers and Their Uses  15.4. Biodegradable and non-biodegradable polymers
  16. Chemistry in Everyday Life  16.1. Drugs and their classification (analgesics, antipyretics, antibiotics, antacids)  16.2. Chemicals in food and cosmetics (preservatives, artificial sweeteners, antioxidants)  16.3. Cleaning agents and detergents (soaps, synthetic detergents, surfactants)  16.4. Environmental Chemistry (Pollution, Green Chemistry, Sustainable Chemistry)

Grade 12 → Aldehydes, ketones and carboxylic acids ↓


Preparation and properties of aldehydes and ketones


Aldehydes and ketones are organic compounds that contain a carbonyl functional group, which is a carbon atom double bonded to an oxygen atom (C=O). This group plays an important role in the chemistry of aldehydes and ketones, affecting their reactivity and properties. Understanding the preparation and properties of these compounds is essential in organic chemistry.

Oxidation of primary alcohols

Aldehydes can be formed by oxidizing primary alcohols. This is usually done using oxidizing agents such as pyridinium chlorochromate (PCC) or Dess-Martin pyridine, which allow selective oxidation of alcohols.

RCH2OH + [O] → RCHO + H2O

For example, ethanol can be oxidized to ethanol:

CH3CH2OH + [O] → CH3CHO + H2O

Hydroformylation of alkenes

Alkenes can be converted into aldehydes by reacting with carbon monoxide and hydrogen in the presence of a catalyst. This process is known as hydroformylation.

RCH=CH2 + CO + H2 → RCH2CH2CHO

Hydroformylation is used on a large scale in industry to produce aldehydes.

Oxidation of secondary alcohols

Ketones can be formed by oxidizing secondary alcohols. Common oxidizing agents include acidic potassium dichromate.

R2CHOH + [O] → R2CO + H2O

For example, cyclohexanol can be oxidized to cyclohexanone:

C6H11OH + [O] → C6H10O + H2O

Friedel–Crafts acylation

In the Friedel-Crafts acylation an acyl group is inserted into an aromatic ring to form a ketone. This is usually achieved using acid chlorides in the presence of a Lewis acid catalyst such as aluminum chloride (AlCl3).

C6H6 + RCOCl → C6H5COR

Benzene reacts with acetyl chloride to form acetophenone:

C6H6 + CH3COCl → C6H5COCH3 + HCl

Physical properties

The presence of the carbonyl group gives aldehydes and ketones unique physical properties. They have higher boiling points than hydrocarbons of similar molecular weight due to the polarity of the carbonyl group, which allows dipole-dipole interactions. However, they have lower boiling points than alcohols because they cannot form hydrogen bonds with each other.

Boiling point

Chemical properties

Nucleophilic addition reactions

The carbon in the carbonyl group is electrophilic and susceptible to attack by nucleophiles. This is the basis for nucleophilic addition reactions, which are common reactions for aldehydes and ketones.

Cyanohydrin formation

When aldehydes or ketones react with hydrogen cyanide (HCN), they form cyanohydrins.

RCHO + HCN → RCH(OH)CN

Reduction to alcohol

Aldehydes and ketones can be reduced to their corresponding alcohols using reducing agents such as lithium aluminium hydride (LiAlH4) or sodium borohydride (NaBH4).

RCHO + H2 → RCH2OH R2CO + H2 → R2CH(OH)

Oxidation reactions

Aldehydes are easily oxidized to carboxylic acids in the presence of oxidizing agents such as potassium permanganate (KMnO4) or chromic acid. However, ketones are generally resistant to oxidation without breaking the C-C bond.

Aldehydes and ketones are valuable in a variety of fields, including industry and biology. Aldehydes such as formaldehyde are used in the manufacture of plastics and resins. Acetone, a well-known ketone, is used as a solvent in cleaning and in the textile industry. These compounds are also present in a variety of biochemical pathways and are important intermediates in organic synthesis.

The preparation and properties of aldehydes and ketones are fundamental concepts in chemistry. The methods for preparing these compounds - oxidation of alcohols, hydroformylation of alkenes, and Friedel-Crafts acylation - along with their physical and chemical properties make them versatile and widely used in chemical processes and industrial applications.


Grade 12 → 12.2


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Structure and nomenclature in aldehydes, ketones and carboxylic acids
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Chemical reactions in aldehydes, ketones and carboxylic acids (nucleophilic addition, oxidation and reduction)

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Preparation and properties of aldehydes and ketones

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