Alcohols
Alcohols
SB p.287The word "alcohol" in everyday speech means one specific liquid — but in chemistry it names an entire family. alcohols are an important class of organic compounds: a homologous-series whose members all carry the –OH functional group covalently bonded to a carbon chain. What people commonly call "alcohol" is just one member of that family — the drink industry's ethanol — and even that molecule should properly be called ethanol, C₂H₅OH, or better, showing the structure, CH₃CH₂OH. Every chemistry idea you already own from the organic chapters — formula types, series behaviour, the reactivity that a functional-group confers — transfers directly to this family; the –OH group simply replaces the C=C handle of the alkenes (u4:c25) as the reactive site everything else happens at.
The family is small at this level and its chemistry is organised around one member. You will draw and name the first four alcohols, then watch ethanol — the family's representative — do three characteristic things: burn, oxidise to ethanoic acid (three different ways, one of them in a wine bottle), and get manufactured industrially by two competing routes whose trade-offs the comparison section sets side by side. Every specification statement of this chapter — 4.29C to 4.33C — is chemistry-only content, assessed in Paper 2C alone, so this lesson is paper-2 territory through and through.
This chapter builds directly on the hydration of ethene you met in the previous lesson (u4:c25) — ethanol's industrial route in — and on the organic toolkit from the introduction (u4:c22): homologous series, functional groups, isomerism, formula types. The –OH group's covalent O–H bond leans on the covalent bonding model (u1:c08), and the combustion equation in Section 3 reuses the balancing discipline from the formulae chapters (u1:c05).