NCERT Solutions for Class 11 Chemistry Chapter 8 Organic Chemistry: Basic Principles & Techniques

Short Note:

• Organic compounds are classified based on structure into acyclic (open chain) and cyclic (closed chain) compounds, and further into homologous series based on functional groups.

• IUPAC nomenclature follows systematic rules using a root word (indicating number of carbon atoms), primary suffix (indicating saturation), and secondary suffix/prefix (indicating functional groups).

Short Note:

• Inductive Effect: the permanent displacement of a sigma bond electron pair towards a more electronegative atom, decreasing with distance along the chain.

• Resonance Effect: delocalisation of pi electrons or lone pairs, represented by multiple contributing structures (resonance structures) of a molecule.

• Electromeric Effect: temporary effect seen in multiple bonds in the presence of an attacking reagent. Hyperconjugation: delocalisation of electrons in a C–H sigma bond adjacent to a positively charged carbon or a multiple bond.

Short Note:

• Common reaction types: substitution, addition, elimination, and rearrangement reactions.

• Key reactive intermediates: carbocations (positively charged carbon), carbanions (negatively charged carbon), and free radicals (unpaired electron species).

Short Note:

• Purification methods include crystallisation, sublimation, distillation, differential extraction, and chromatography (for separating mixtures based on differing physical/chemical properties).

• Qualitative tests: Lassaigne's Test is used to detect nitrogen, sulphur, and halogens in an organic compound by converting them into ionic forms via fusion with sodium metal.