Alcohols — FAQ

In an alcohol, the hydroxyl (–OH) group is attached to a saturated carbon atom (part of an alkyl group). In a phenol, the –OH group is attached directly to a carbon atom within a benzene ring. This difference leads to significantly different chemical properties, particularly in terms of acidity.

Yes, potassium manganate(VII) ($KMnO_4$) is a powerful oxidising agent and will oxidise primary and secondary alcohols. The colour change is from purple ($MnO_4^-$) to colourless ($Mn^{2+}$). However, it is less selective than dichromate(VI) and can easily cause cleavage of C-C bonds, especially under harsh conditions. For A-Level purposes, acidified potassium dichromate(VI) is the standard reagent you should refer to unless specified otherwise.

Esterification is a slow, reversible reaction. The strong acid catalyst (e.g., concentrated $H_2SO_4$) serves two purposes: it speeds up both the forward and reverse reactions, allowing equilibrium to be reached faster. It also acts as a dehydrating agent, removing the water produced, which shifts the equilibrium position to the right (according to Le Chatelier's principle), increasing the yield of the ester.