Q.Secondary alcohol is

Alcohols are classed by the NUMBER of -OH groups (monohydric, e.g. ethanol; dihydric, e.g. glycol; trihydric, e.g. glycerol; and, more generally, polyhydric, e.g. sorbitol) and by the TYPE of carbon bearing the -OH (primary, secondary or tertiary, on an sp3 carbon; allylic, next to a C=C; or benzylic, next to an aromatic ring). Two related-looking structures are explicitly excluded from being 'alcohols': -OH on an sp2 alkene carbon (vinyl alcohol, CH2=CH-OH, which tautomerises to acetaldehyde) and -OH directly on an aromatic ring (a phenol, with entirely different acidity and reactivity, covered as its own family in this unit). …