Dehydrogenation occurs in alcohol oxidation, involving the cleavage of O-H and C-H bonds. Primary alcohols oxidize to aldehydes or carboxylic acids, depending on the oxidizing agent. Strong agents like acidified potassium permanganate yield carboxylic acids directly.

Dehydration of alcohols, leading to the formation of alkenes, occurs with protic acids (e.g., concentrated H₂SO₄ or H₃PO₄) or catalysts like anhydrous zinc chloride or alumina. The relative ease of dehydration follows the order: Tertiary > Secondary > Primary.

Phosphorus tribromide is used to convert alcohols to alkyl bromides. This reaction differs from the Lucas test, offering an alternative method for the transformation of alcohols into halides.

Alcohols react with hydrogen halides to form alkyl halides. The Lucas test, using Lucas reagent (conc. HCl and ZnCl₂), distinguishes between alcohol classes based on the time taken for turbidity to appear; tertiary alcohols show immediate turbidity, while primary alcohols ...

Alkenes undergo acid-catalyzed hydration in the presence of water and acid catalyst, forming alcohols. In the case of unsymmetrical alkenes, the addition follows Markovnikov’s rule.