9. Organic Chemistry
(i) Introduction to Organic compounds.
- Unique nature of Carbon atom – tetra valency, catenation.
- Formation of single, double and triple bonds, straight chain, branched chain, cyclic compounds (only benzene structure).
(ii) Structure and Isomerism.
- Structure of compounds with single, double and triple bonds.
- Structural formulae of hydrocarbons. Structural formula must be given for: alkanes, alkenes, alkynes up to 5 carbon atoms.
- Isomerism – structural (chain, position).
(iii) Homologous series – characteristics with examples. Alkane, alkene, alkyne series and their gradation in properties and the relationship with the molecular mass or molecular formula.
(iv) Simple nomenclature. Simple nomenclature of the hydrocarbons with simple functional groups – (halides, double bond, triple bond, alcoholic, aldehydic, carboxylic ketone, ether and ester) longest chain rule and smallest number for functional groups rule – trivial and IUPAC names (compounds with only one functional group).
(v) Hydrocarbons: alkanes, alkenes, alkynes.
- Alkanes - general formula; methane (greenhouse gas) and ethane - methods of preparation from sodium ethanoate (sodium acetate), sodium propanoate (sodium propionate), from iodomethane (methyl iodide) and bromoethane (ethyl bromide). Complete and incomplete combustion of methane and ethane, reaction of methane and ethane with chlorine through substitution.
- Alkenes – (unsaturated hydrocarbons with a double bond); ethene as an example. Methods of preparation of ethene by dehydro halogenation reaction and dehydration reactions.
- Alkynes - (unsaturated hydrocarbons with a triple bond); ethyne as an example of alkyne; Methods of preparation from calcium carbide and 1,2 dibromoethane (ethylene dibromide). Only main properties, particularly addition products with hydrogen and halogen namely Cl₂, Br₂ and I₂ pertaining to alkenes and alkynes.
- Uses of methane, ethane, ethene, ethyne.
(vi) Alcohols: ethanol – preparation, properties and uses.
- Preparation of ethanol by hydrolysis of alkyl halide.
- Properties – Physical: Nature, Solubility, Density, Boiling Points. Chemical: Combustion, action with sodium, ester formation with acetic acid, dehydration with conc. Sulphuric acid to prepare ethene.
- Denatured, methylated alcohol or spirit and spurious alcohol.
- Important uses of Ethanol.
(vii) Carboxylic acids (aliphatic - mono carboxylic acid): Acetic acid – properties and uses of acetic acid.
- Structure of acetic acid.
- Properties of Acetic Acid: Physical properties – odour (vinegar), glacial acetic acid (effect of sufficient cooling to produce ice like crystals). Chemical properties – action with litmus, alkalis and alcohol (idea of esterification).
- Uses of acetic acid.