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 → Alcohol, phenol and ether ↓


Preparation and properties of alcohols


Introduction

Alcohols are organic compounds containing one or more hydroxyl (-OH) groups attached to a carbon atom. The general formula of alcohols is CnH2n+1OH. They are versatile in nature and have various applications in industries and daily life.

Preparation of alcohol

There are several methods for preparing alcohol, including fermentation, hydration of alkenes, and reduction of carbonyl compounds.

1. Fermentation

Fermentation is one of the oldest methods for producing alcohol, particularly ethanol. It involves converting sugars into alcohol and carbon dioxide by the action of yeast or bacteria.

C6H12O6 (glucose) --yeast--> 2 C2H5OH (ethanol) + 2 CO2

2. Hydration of alkenes

Alcohols can be formed by hydrating alkenes. This process involves the addition of water to the double bond in the presence of an acid catalyst.

Mechanism:

  1. Formation of carbocation by protonation of alkene
  2. Attack of water on the carbocation
  3. Deprotonation to form alcohols
CH2=CH2 --H2O/H+ --> CH3CH2OH

Example: Ethene can be converted into ethanol using this method.

3. Reduction of carbonyl compounds

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

RCHO + 2 [H] --LiAlH4 --> RCH2OH (primary alcohol)
    
RCOR' + 2 [H] --NaBH4 --> RCH(OH)R' (secondary alcohol)

Example 1: Acetaldehyde when reduced gives ethanol.

Example 2: Acetone when reduced forms isopropanol.

Properties of alcohol

Alcohols exhibit unique physical and chemical properties due to the presence of the hydroxyl group.

1. Physical properties

  • Boiling point: Alcohols have a higher boiling point than hydrocarbons of the same molecular weight. This is due to hydrogen bonding between alcohol molecules.
  • Solubility: The following alcohols are soluble in water due to hydrogen bonding. Solubility decreases as the length of the carbon chain increases.
  • Odour: Many alcohols have a distinctive odour, for example, methanol has a slight alcohol-like odour, while ethanol has a spirit-like odour.
Comparison: Methanol ( CH3OH) is more soluble in water than octanol ( CH3(CH2)7OH).

2. Chemical properties

Alcohols can undergo a variety of chemical reactions, which are useful for the synthesis of other compounds.

a) Dehydration

When heated with a strong acid such as sulfuric acid, alcohols can lose a water molecule to form an alkene.

CH3CH2OH --H2SO4/heat--> CH2=CH2 + H2O

Example: Ethylene can be formed by dehydrating ethanol.

b) Oxidation

Depending on the type of alcohol and the conditions, alcohols can be oxidized to form aldehydes, ketones, or carboxylic acids.

RCH2OH (primary alcohol) --[O]--> RCHO (aldehyde) --[O]--> RCOOH (carboxylic acid)
    
R2CHOH (secondary alcohol) --[O]--> R2CO (ketone)

Example 1: Ethanol can be oxidized to acetaldehyde and further to acetic acid.

Example 2: Isopropanol can be oxidized to acetone.

c) Esterification

Alcohols react with carboxylic acids in the presence of an acidic catalyst to form esters and water.

RCOOH + R'OH --H2SO4 --> RCOOR' + H2O

Example: Ethanol and acetic acid react to form ethyl acetate.

Conclusion

Alcohols are essential compounds in organic chemistry, with varied preparation methods and a wide range of physical and chemical properties. Understanding these properties allows chemists to use alcohols in a variety of industrial and laboratory applications.

A visual example

Ethanol: C2H5OH Dehydration: forms ethylene (C2H4) Oxidation: forms acetic acid ( CH3COOH ) Esterification: forms ethyl acetate (CH3COOCH2CH3)

Grade 12 → 11.2


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Structure and classification of alcohols, phenols and ethers
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Preparation and properties of alcohols

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