Name an aliphatic compound by IUPAC rules, sort its isomers, tell a nucleophile from an electrophile, and rank carbocations, radicals and carbanions by stability using inductive and resonance effects.
Unit 3, Organic chemistry, carries 17 of the 50 chemistry marks — the heaviest unit in the subject. With eleven chapters sharing them, this one averages a little over one and a half (MEC publishes weights by unit, not by chapter). Its real value is larger: every later organic chapter is written in this chapter's vocabulary.
MEC scope: Tetra-covalency and catenation of carbon; Classification of organic compounds, alkyl and aryl groups, functional groups, homologous series; IUPAC nomenclature of aliphatic compounds; Isomerism; Heterolytic and homolytic bond fission; Electrophiles, nucleophiles, carbocations, carbanions and free radicals; Inductive and resonance effects.
Three ways it is asked:
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