Chapter 16: Organic Chemistry

Central to understanding organic chemistry is carbon's exceptional ability to form four covalent bonds and create diverse molecular architectures including linear chains, branched structures, and cyclic systems. Hydrocarbons, the simplest class of organic molecules composed exclusively of carbon and hydrogen atoms, are classified based on bonding types: alkanes contain only single bonds between carbon atoms and represent fully saturated compounds, alkenes incorporate carbon-carbon double bonds creating unsaturated systems, and alkynes feature triple bonds between carbons. The chapter emphasizes systematic nomenclature using IUPAC naming conventions, teaching students to identify main carbon chains, apply numerical prefixes corresponding to chain length, and designate substituent groups and alkyl branches with proper positioning. Structural isomerism is introduced as a critical concept showing how compounds sharing identical molecular formulas can possess entirely different atomic connectivity and thus different properties. Cycloalkanes and their distinctive naming requirements are examined alongside methods for representing molecular structures in various formats including condensed formulas, expanded structural drawings, and skeletal line notations. Physical properties of alkanes such as boiling point trends, solubility characteristics, and combustion reactivity are connected to molecular structure and intermolecular forces. The chapter concludes with practical applications demonstrating how fundamental hydrocarbon chemistry explains the behavior of fuels, natural gas composition, petroleum refining processes, and atmospheric chemistry of compounds like methane. These foundational concepts provide essential knowledge for understanding more complex organic molecules and their biological roles.